[1] The frequency of direct current is .
A.
Zero
B.
50 HZ
C.
60 HZ
D.
100 HZ
Ans:
Zero
Explanation :
Direct Current (DC) refers to power systems that use only one polarity of voltage or current, and to refer to the constant, zero-frequency, or slowly varying local mean value of a voltage or current.
[2] For photoelectric effect to take place, the metal used as the cathode should have –
A.
high melting point
B.
low melting point
C.
low work function
D.
low resistance
Ans:
low work function
Explanation :
The photoelectric effect is the propensity of high-energy electromagnetic radiation to eject electrons from a given material. The photoelectric effect has been utilized in devices called photocells, consisting of two electrodes in a sealed vacuum tube.
[3] If electric resistance is to be decreased, then the number of resistances should be connected in –
A.
Series
B.
Parallel
C.
Mixed arrangement
D.
None of these
Ans:
Parallel
Explanation :
Resistors are in parallel when each resistor is connected directly to the voltage source by connecting wires having negligible resistance. Each resistor thus has the full voltage of the source applied to it. When resistors are connected in parallel, more current flows from the source than would flow for any of them individually, so the total resistance is lower. Each resistor in parallel has the same full voltage of the source applied to it, but divide the total current amongst them
[4] The material used in electric heater is –
A.
Tungsten
B.
Nichrome
C.
Brass
D.
Steel
Ans:
Nichrome
Explanation :
Due to its resistance to oxidation and stability at high temperatures, Nichrome is widely used in electic heating elements, such as in appliances and tools. Typically, nichrome is wound in coils to a certain electrical resistance, and current is passed through it to produce heat.
[5] The rate of change of displacement is called:
A.
Acceleration
B.
Speed
C.
Distance
D.
Velocity
Ans:
Velocity
Explanation :
In considering motions of objects over time the instantaneous velocity of the object is the rate of change of the displacement as a function of time.
[6] The direction of heat flow between two objects depends on -
A.
Their masses
B.
Their heat contents
C.
Their temperatures
D.
Whether they are in solid, liquid or gaseous state
Ans:
Their temperatures
Explanation :
Heat always flows from a body at higher temperature to a body at a lower temperature.
[7] A man in a train moving with a constant velocity drops a ball on the platform. The path of the ban as seen by an observer standing on the platform is –
A.
A straight line
B.
A circle
C.
A parabola
D.
None of these
Ans:
A parabola
Explanation :
In the reference frame of the platform the ball has initial horizontal velocity equal to the velocity of the train. The vertical direction is the same observed on the train because both observers agree that gravity is acting on the ball causing an acceleration g.
[8] Which of the following is responsible for permanent hardness of water?
A.
magnesium bicarbonate
B.
sodium chloride
C.
calcium sulphate
D.
calcium bicarbonate
Ans:
calcium sulphate
Explanation :
Permanent hardness is caused by dissolved calcium sulfate (which is not removed by boiling). Hard water contains dissolved magnesium and calcium ions. These make it more difficult for the water to form lather with soap. Temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling)
[9] While ascending a hill, the driver of the vehicle keeps the gear ratio –
A.
equal to 1
B.
less than 1
C.
greater than 1
D.
either equal to or greater than 1
Ans:
either equal to or greater than 1
Explanation :
While ascending a hill Gear Ratio should be "Either equal to or greater than 1?. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of output gear. It prevents the vehicle from stalling.
[10] A wire of resistance R is cut into ‘n’ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be –
A.
nR
B.
R/n
C.
n/R
D.
R/n²
Ans:
R/n²
Explanation :
Since R is directly proportional to length of the wire, when wire is cut into equal parts, then Resistance of each part = R/n
[11] What is unit of Electrical Capacity?
A.
henry
B.
farad
C.
volt
D.
ohm
Ans:
farad
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
Direct Current (DC) refers to power systems that use only one polarity of voltage or current, and to refer to the constant, zero-frequency, or slowly varying local mean value of a voltage or current.
[2] For photoelectric effect to take place, the metal used as the cathode should have –
A.
high melting point
B.
low melting point
C.
low work function
D.
low resistance
Ans:
low work function
Explanation :
The photoelectric effect is the propensity of high-energy electromagnetic radiation to eject electrons from a given material. The photoelectric effect has been utilized in devices called photocells, consisting of two electrodes in a sealed vacuum tube.
[3] If electric resistance is to be decreased, then the number of resistances should be connected in –
A.
Series
B.
Parallel
C.
Mixed arrangement
D.
None of these
Ans:
Parallel
Explanation :
Resistors are in parallel when each resistor is connected directly to the voltage source by connecting wires having negligible resistance. Each resistor thus has the full voltage of the source applied to it. When resistors are connected in parallel, more current flows from the source than would flow for any of them individually, so the total resistance is lower. Each resistor in parallel has the same full voltage of the source applied to it, but divide the total current amongst them
[4] The material used in electric heater is –
A.
Tungsten
B.
Nichrome
C.
Brass
D.
Steel
Ans:
Nichrome
Explanation :
Due to its resistance to oxidation and stability at high temperatures, Nichrome is widely used in electic heating elements, such as in appliances and tools. Typically, nichrome is wound in coils to a certain electrical resistance, and current is passed through it to produce heat.
[5] The rate of change of displacement is called:
A.
Acceleration
B.
Speed
C.
Distance
D.
Velocity
Ans:
Velocity
Explanation :
In considering motions of objects over time the instantaneous velocity of the object is the rate of change of the displacement as a function of time.
[6] The direction of heat flow between two objects depends on -
A.
Their masses
B.
Their heat contents
C.
Their temperatures
D.
Whether they are in solid, liquid or gaseous state
Ans:
Their temperatures
Explanation :
Heat always flows from a body at higher temperature to a body at a lower temperature.
[7] A man in a train moving with a constant velocity drops a ball on the platform. The path of the ban as seen by an observer standing on the platform is –
A.
A straight line
B.
A circle
C.
A parabola
D.
None of these
Ans:
A parabola
Explanation :
In the reference frame of the platform the ball has initial horizontal velocity equal to the velocity of the train. The vertical direction is the same observed on the train because both observers agree that gravity is acting on the ball causing an acceleration g.
[8] Which of the following is responsible for permanent hardness of water?
A.
magnesium bicarbonate
B.
sodium chloride
C.
calcium sulphate
D.
calcium bicarbonate
Ans:
calcium sulphate
Explanation :
Permanent hardness is caused by dissolved calcium sulfate (which is not removed by boiling). Hard water contains dissolved magnesium and calcium ions. These make it more difficult for the water to form lather with soap. Temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling)
[9] While ascending a hill, the driver of the vehicle keeps the gear ratio –
A.
equal to 1
B.
less than 1
C.
greater than 1
D.
either equal to or greater than 1
Ans:
either equal to or greater than 1
Explanation :
While ascending a hill Gear Ratio should be "Either equal to or greater than 1?. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of output gear. It prevents the vehicle from stalling.
[10] A wire of resistance R is cut into ‘n’ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be –
A.
nR
B.
R/n
C.
n/R
D.
R/n²
Ans:
R/n²
Explanation :
Since R is directly proportional to length of the wire, when wire is cut into equal parts, then Resistance of each part = R/n
[11] What is unit of Electrical Capacity?
A.
henry
B.
farad
C.
volt
D.
ohm
Ans:
farad
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
Resistors are in parallel when each resistor is connected directly to the voltage source by connecting wires having negligible resistance. Each resistor thus has the full voltage of the source applied to it. When resistors are connected in parallel, more current flows from the source than would flow for any of them individually, so the total resistance is lower. Each resistor in parallel has the same full voltage of the source applied to it, but divide the total current amongst them
[4] The material used in electric heater is –
A.
Tungsten
B.
Nichrome
C.
Brass
D.
Steel
Ans:
Nichrome
Explanation :
Due to its resistance to oxidation and stability at high temperatures, Nichrome is widely used in electic heating elements, such as in appliances and tools. Typically, nichrome is wound in coils to a certain electrical resistance, and current is passed through it to produce heat.
[5] The rate of change of displacement is called:
A.
Acceleration
B.
Speed
C.
Distance
D.
Velocity
Ans:
Velocity
Explanation :
In considering motions of objects over time the instantaneous velocity of the object is the rate of change of the displacement as a function of time.
[6] The direction of heat flow between two objects depends on -
A.
Their masses
B.
Their heat contents
C.
Their temperatures
D.
Whether they are in solid, liquid or gaseous state
Ans:
Their temperatures
Explanation :
Heat always flows from a body at higher temperature to a body at a lower temperature.
[7] A man in a train moving with a constant velocity drops a ball on the platform. The path of the ban as seen by an observer standing on the platform is –
A.
A straight line
B.
A circle
C.
A parabola
D.
None of these
Ans:
A parabola
Explanation :
In the reference frame of the platform the ball has initial horizontal velocity equal to the velocity of the train. The vertical direction is the same observed on the train because both observers agree that gravity is acting on the ball causing an acceleration g.
[8] Which of the following is responsible for permanent hardness of water?
A.
magnesium bicarbonate
B.
sodium chloride
C.
calcium sulphate
D.
calcium bicarbonate
Ans:
calcium sulphate
Explanation :
Permanent hardness is caused by dissolved calcium sulfate (which is not removed by boiling). Hard water contains dissolved magnesium and calcium ions. These make it more difficult for the water to form lather with soap. Temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling)
[9] While ascending a hill, the driver of the vehicle keeps the gear ratio –
A.
equal to 1
B.
less than 1
C.
greater than 1
D.
either equal to or greater than 1
Ans:
either equal to or greater than 1
Explanation :
While ascending a hill Gear Ratio should be "Either equal to or greater than 1?. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of output gear. It prevents the vehicle from stalling.
[10] A wire of resistance R is cut into ‘n’ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be –
A.
nR
B.
R/n
C.
n/R
D.
R/n²
Ans:
R/n²
Explanation :
Since R is directly proportional to length of the wire, when wire is cut into equal parts, then Resistance of each part = R/n
[11] What is unit of Electrical Capacity?
A.
henry
B.
farad
C.
volt
D.
ohm
Ans:
farad
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
In considering motions of objects over time the instantaneous velocity of the object is the rate of change of the displacement as a function of time.
[6] The direction of heat flow between two objects depends on -
A.
Their masses
B.
Their heat contents
C.
Their temperatures
D.
Whether they are in solid, liquid or gaseous state
Ans:
Their temperatures
Explanation :
Heat always flows from a body at higher temperature to a body at a lower temperature.
[7] A man in a train moving with a constant velocity drops a ball on the platform. The path of the ban as seen by an observer standing on the platform is –
A.
A straight line
B.
A circle
C.
A parabola
D.
None of these
Ans:
A parabola
Explanation :
In the reference frame of the platform the ball has initial horizontal velocity equal to the velocity of the train. The vertical direction is the same observed on the train because both observers agree that gravity is acting on the ball causing an acceleration g.
[8] Which of the following is responsible for permanent hardness of water?
A.
magnesium bicarbonate
B.
sodium chloride
C.
calcium sulphate
D.
calcium bicarbonate
Ans:
calcium sulphate
Explanation :
Permanent hardness is caused by dissolved calcium sulfate (which is not removed by boiling). Hard water contains dissolved magnesium and calcium ions. These make it more difficult for the water to form lather with soap. Temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling)
[9] While ascending a hill, the driver of the vehicle keeps the gear ratio –
A.
equal to 1
B.
less than 1
C.
greater than 1
D.
either equal to or greater than 1
Ans:
either equal to or greater than 1
Explanation :
While ascending a hill Gear Ratio should be "Either equal to or greater than 1?. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of output gear. It prevents the vehicle from stalling.
[10] A wire of resistance R is cut into ‘n’ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be –
A.
nR
B.
R/n
C.
n/R
D.
R/n²
Ans:
R/n²
Explanation :
Since R is directly proportional to length of the wire, when wire is cut into equal parts, then Resistance of each part = R/n
[11] What is unit of Electrical Capacity?
A.
henry
B.
farad
C.
volt
D.
ohm
Ans:
farad
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
In the reference frame of the platform the ball has initial horizontal velocity equal to the velocity of the train. The vertical direction is the same observed on the train because both observers agree that gravity is acting on the ball causing an acceleration g.
[8] Which of the following is responsible for permanent hardness of water?
A.
magnesium bicarbonate
B.
sodium chloride
C.
calcium sulphate
D.
calcium bicarbonate
Ans:
calcium sulphate
Explanation :
Permanent hardness is caused by dissolved calcium sulfate (which is not removed by boiling). Hard water contains dissolved magnesium and calcium ions. These make it more difficult for the water to form lather with soap. Temporary hardness is caused by dissolved calcium hydrogen carbonate (which is removed by boiling)
[9] While ascending a hill, the driver of the vehicle keeps the gear ratio –
A.
equal to 1
B.
less than 1
C.
greater than 1
D.
either equal to or greater than 1
Ans:
either equal to or greater than 1
Explanation :
While ascending a hill Gear Ratio should be "Either equal to or greater than 1?. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of output gear. It prevents the vehicle from stalling.
[10] A wire of resistance R is cut into ‘n’ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be –
A.
nR
B.
R/n
C.
n/R
D.
R/n²
Ans:
R/n²
Explanation :
Since R is directly proportional to length of the wire, when wire is cut into equal parts, then Resistance of each part = R/n
[11] What is unit of Electrical Capacity?
A.
henry
B.
farad
C.
volt
D.
ohm
Ans:
farad
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
While ascending a hill Gear Ratio should be "Either equal to or greater than 1?. Gear Ratio is the ratio between angular velocity of input gear to the angular velocity of output gear. It prevents the vehicle from stalling.
[10] A wire of resistance R is cut into ‘n’ equal parts. These parts are then connected in parallel. The equivalent resistance of the combination will be –
A.
nR
B.
R/n
C.
n/R
D.
R/n²
Ans:
R/n²
Explanation :
Since R is directly proportional to length of the wire, when wire is cut into equal parts, then Resistance of each part = R/n
[11] What is unit of Electrical Capacity?
A.
henry
B.
farad
C.
volt
D.
ohm
Ans:
farad
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
Henry is unit of Magnetic Induction, volt is unit of Potential Difference, ohm is unit of Electric Resistance.
[12] Work done upon a body .
A.
only a vector quantity
B.
only a scalar quantity
C.
both vector and scalar
D.
neither vector nor scalar
Ans:
only a scalar quantity
Explanation :
work done due to displacement caused by a force is a scalar quantity. The dot product of vector quantities is always scalar which means it is has only magnitude and no direction.
[13] With the increase of pressure, the boiling point of any substance -
A.
Increases
B.
Decreases
C.
Remains Same
D.
Becomes zero
Ans:
Increases
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point the pressure of the escaping vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.
[14] Supersonic plane fly with the speed -
A.
less than the speed of sound
B.
of sound
C.
greater than the speed of sound
D.
of light
Ans:
greater than the speed of sound
Explanation :
The regimes of flight are subsonic, transonic, supersonic and hypersonic. Vehicles that fly at supersonic speeds are flying faster than the speed of sound. The speed of sound is about 768 miles per hour (1,236 kilometers per hour) at sea level.
[15] When a particle and an antiparticle come in contact with each other, they -
A.
repell each other
B.
annihilate each other
C.
go undisturbed
D.
spin about a common axis
Ans:
annihilate each other
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
When a particle interacts with its antiparticle, the result is the annihilation of both and the generation of other particles. The most common and oft-quoted example of this process is the electron–positron annihilation.
[16] Photon is the fundamental unit/ quantum of –
A.
gravitation
B.
electricity
C.
magnetism
D.
light
Ans:
light
Explanation :
A photon is an elementary particle, the quantum of light and all other forms of electromagnetic radiation. The modern photon concept was developed gradually by Albert Einstein.
[17] Time of exposure required for taking photograph of an object depends upon the –
A.
brightness of the object
B.
skill of photographer
C.
proximity of object
D.
size of the object
Ans:
brightness of the object
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
In photography, shutter speed or exposure time is the effective length of time a camera's shutter is open. The total exposure is proportional to this exposure time, or duration of light reaching the film or image sensor. The correct exposure for a particular object depends on the brightness of the object to be photographed.
[18] The ordinary and maximum tolerance limit of sound by human being is –
A.
50 db to 70 db (decibel)
B.
60 db to 80 db (decibel)
C.
65 db to 75 db (decibel)
D.
70 db to 85 db (decibel)
Ans:
60 db to 80 db (decibel)
Explanation :
Normal speech is about 60 dB (decibels). A dangerous sound is anything that is 80 dB or higher which can lead to hearing loss. At 70 dB or lower, the risk of harm to healthy ears is negligible. Listening to sound above 80 decibels can cause profound deafness.
[19] Which is best used as a sound absorbing material in partition walls?
A.
Stone chips
B.
Steel
C.
Glass - wool
D.
Glass pieces
Ans:
Glass - wool
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
Materials that do not transfer mechanical energy well. These tend to be soft, flexible, low density, and with high surface area to linear area ratios.
[20] The best conductor of electricity among the following is -
A.
copper
B.
iron
C.
aluminum
D.
silver
Ans:
silver
Explanation :
Copper and Silver Are Most Common. Silver is the best conductor of electricity because it contains a higher number of movable atoms (free electrons).
[21] Light Emitting Diodes (LED) is used in fancy electronic devices such as toys emit
A.
X-rays
B.
ultraviolet light
C.
(4) All of the above
D.
radio waves
Ans:
radio waves
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics.
[22] The primary colours in photography are –
A.
Red, Blue, Yellow
B.
Red, Yellow, Green
C.
Red, Blue, Green
D.
Blue, Yellow, Green
Ans:
Red, Blue, Yellow
Explanation :
There are three primary colours of Red, Green and Blue (ROB). As these are mixed they form lighter colours, and when all three are mixed together they appear as white. Artists and graphic designers, who work with paintings and illustrations more than they do with photographs, often refer to Red, Yellow and Blue as the primary colours.
[23] Two electrons in an orbital are differentiated by which of the following?
A.
Magnetic quantum number
B.
Spin quantum number
C.
Principal quantum number
D.
Azimuthal quantum number
Ans:
Spin quantum number
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli Exclusion Principle states that “no two electrons in an atom can have the same four quantum numbers. This means that no two electrons can have the same state in an atom. Each electron must have a different spin or occupy a different shell from any other.
[24] Stress can be defined as quantity.
A.
Scalar
B.
Vector
C.
Phasor
D.
Tensor
Ans:
Tensor
Explanation :
Stress is defined as Resisting force per unit area of an element, on which load is applied. Stress is always perpendicular to a cross-section in the element. It is neither scalar (it cannot be numerically added), nor is it a vector (it does not follow the triangle rule of vector addition). It is a tensor quantity because it describes things happening in two directions simultaneously.
[25] Which of the following property of sound is affected by change in air temperature –
A.
Frequency
B.
Intensity
C.
Amplitude
D.
Wavelength
Ans:
Wavelength
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.
Explanation :
The wavelength of sound changes with temperature. This is because the speed of sound changes with the temperature. Since the speed of sound is different at different temperature, this means the wavelength of sound at a given frequency is a variable depending on the speed of sound. For example, the wavelength of a 100 cycle tone in air at 68°F would be 11.27 feet while the same tone in fresh water at 68°F would have a wavelength of 48.05 feet.