Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

The voice of women is thinner than that of men, because the voice of women. . . . .

A. the frequency is higher
B. has a longer wavelength
C. has more dimensions
D. velocity is greater
Answer» B. has a longer wavelength
2.

When two loudspeakers are played simultaneously at a place, the listener sitting at a particular place does not hear their sound, because of this?

A. reflection
B. interference
C. refraction
D. resonance
Answer» C. refraction
3.

Infrared waves are mechanical waves whose frequency is . . . . .

A. exceeds 20, 000 Hz
B. is greater than 10, 000 Hz
C. is greater than 1,000 Hz
D. less than 20 Hz
Answer» E.
4.

Acoustic is science?

A. Relating to light
B. Related to sound
C. Related to climate
D. Related to metal
Answer» C. Related to climate
5.

speed of sound in air

A. decreases with increase in temperature
B. increases with decrease in temperature
C. does not depend on temperature
D. decreases with a decrease in temperature
Answer» E.
6.

Which of the following type of wave is used in night vision device?

A. Radio wave
B. micro wave
C. infrared wave
D. none of these
Answer» D. none of these
7.

When sound waves travel, what do they take with them?

A. mass
B. sound
C. energy
D. Potential difference
Answer» D. Potential difference
8.

In which medium will the speed of sound be maximum at a temperature of about 20°C?

A. air
B. granite
C. Water
D. Iron
Answer» E.
9.

What is echo sounding used for?

A. to vibrate sound
B. to increase the frequency of sound
C. to measure the depth of the ocean
D. none of the above
Answer» D. none of the above
10.

The reason for the resonance?

A. reflection of sound
B. refraction of sound
C. sound absorption
D. speed of sound
Answer» B. refraction of sound
11.

The difference between the velocity of an object and the velocity of sound in the same medium and under the same conditions is called?

A. durability number
B. Laplace number
C. octane number
D. mac number
Answer» E.
12.

Which of the following causes maximum noise pollution?

A. Car
B. railway engine
C. pop music
D. fly a plane
Answer» E.
13.

What are Ultra Sonic Waves?

A. Longitudinal waves of frequency 1000 to 10, 000 Hz
B. Transverse waves of frequency 1000 to 10, 000 Hz
C. Transverse waves of frequency greater than 20, 000 Hz
D. Longitudinal waves of frequency greater than 20, 000 Hz
Answer» E.
14.

It is said that when Tansen sang, the glass of the window or the glass glass used to break into pieces. If this is possible, then what quality of sound would it be due to?

A. reflection
B. refraction
C. resonance
D. interference
Answer» D. interference
15.

Two people cannot listen to each other on the surface of the moon, because . . . . . . . . . . .

A. their ears stop working on the moon
B. there is no atmosphere on the moon
C. They wear a special type of space suit on the moon.
D. sound travels very slowly on the moon
Answer» C. They wear a special type of space suit on the moon.
16.

The Dead Hall has a survival period

A. Zero seconds
B. 0 . 8 seconds
C. 8 seconds
D. 8 seconds
Answer» B. 0 . 8 seconds
17.

When we keep the jug under water to fill, we hear a special kind of sound as the jug is filled. this is due to -

A. diffraction
B. Translation
C. interference
D. reflection
Answer» D. reflection
18.

What is the decibel unit used for?

A. to the speed of light
B. for heat intensity
C. for sound intensity
D. for the frequency of the radio wave
Answer» D. for the frequency of the radio wave
19.

The voice of women is louder than that of men , because of the voice of women . . . . . . . . .

A. Dimensions decrease
B. dimension is greater
C. low voltage
D. the pitch is higher
Answer» E.
20.

The fluctuation in the frequency of a sound source is called?

A. of Raman effect
B. of doppler effect
C. of crompton effect
D. photoelectric effect
Answer» C. of crompton effect
21.

While shouting, the person always keeps the palm close to the mouth, because . . . . . . . .

A. In that case the sound energy will point in only one direction.
B. sonic fullness of sound increases
C. fluctuating sound tone increases
D. This action has no effect on the sound
Answer» B. sonic fullness of sound increases
22.

The reason why a woman's voice is sharper than a man's voice is?

A. higher frequency
B. lower frequency
C. higher dimension
D. Weak speech - fiber
Answer» B. lower frequency
23.

The whistling sound of an approaching train increases, while it decreases for a train going farther away. Is this an example?

A. of Raman effect
B. water-thomson effect
C. of crompton effect
D. of doppler effect
Answer» E.
24.

Which of the following statements is true for sound waves?

A. they can be polarized
B. Can it work in vacuum?
C. Their speed is 332 m per second at 0 °C.
D. all the above statements are true
Answer» D. all the above statements are true
25.

What is the frequency of infrared waves?

A. less than 20 Hz
B. over 20 Hz
C. over 20 , 000 Hz
D. 20 Hz 20,000 Hz
Answer» B. over 20 Hz
26.

Velocity of sound in different mediums

A. varies and is highest in solids
B. varies and is lowest in liquids
C. varies and is highest in gas
D. varies and is highest in vacuum
Answer» B. varies and is lowest in liquids
27.

Which characteristic of sound makes a sound thick or thin?

A. intensity
B. Equilibrium
C. quality
D. none of these
Answer» C. quality
28.

Explosion is not heard on the moon far from the surface -

A. Due to absence of atmosphere
B. due to the decrease in the gravity of the moon
C. Because of the low intensity of sound waves
D. none of the above
Answer» B. due to the decrease in the gravity of the moon
29.

Do supersonic planes fly?

A. at the speed of sound
B. less than the speed of sound
C. at the speed of light
D. faster than the speed of sound
Answer» E.
30.

Why is the voice of a young child more beloved than the voice of a young man?

A. The pitch of a child's voice is lower than that of a man's voice
B. The pitch of a child's voice is higher than that of a man's voice.
C. child has more power
D. none of the above
Answer» C. child has more power
31.

Bats can fly in the dark because . . . .

A. it can be seen clearly in the dark
B. the pupil of his eye is very large
C. she produces very strong waves that control her
D. any bird can do this
Answer» D. any bird can do this
32.

If the same note is played on sitar and flute, then the sound produced by it can be distinguished due to the difference in the following?

A. 224 feet
B. 56 feet
C. 28 feet
D. 100 feet
Answer» C. 28 feet
33.

When the army crosses the bridge , the soldiers are instructed not to walk step by step , because . . . . . . .

A. There is a risk of bridge breaking due to increased pressure
B. There is a danger of breaking the bridge due to the resonance of the sound produced by the feet.
C. There is a risk of bridge breaking due to the Doppler effect
D. none of the above
Answer» C. There is a risk of bridge breaking due to the Doppler effect
34.

Sonar is mostly used in?

A. by astronauts
B. by doctors
C. by engineers
D. by navigators
Answer» E.
35.

Which of the following effect is not found in sound waves?

A. Polarization
B. reflection
C. interference
D. diffraction
Answer» B. reflection
36.

Sound travels at the maximum speed?

A. in water
B. in steel
C. into the void
D. in hydrogen
Answer» C. into the void
37.

How many decibels of sound are produced when two people talk to each other?

A. about 5 decibels
B. about 10 decibels
C. about 30 decibels
D. about 100 decibels
Answer» D. about 100 decibels
38.

What is the tolerance limit of noise for humans?

A. 45 decibels
B. 85 decibels
C. 125 decibels
D. 155 decibels
Answer» C. 125 decibels
39.

In which medium does sound travel faster?

A. air
B. Clean water
C. Vacuum
D. in iron
Answer» E.
40.

In which medium the speed of sound is maximum?

A. Vacuum
B. Solid
C. fluid
D. gas
Answer» C. fluid
41.

What is the speed of sound in air?

A. 664 m / sec
B. 332 m / sec
C. 166 m / sec
D. 100 m / sec
Answer» C. 166 m / sec
42.

The heat required to change the unit mass of a solid substance from solid to liquid at its melting point is called?

A. melting point of solid
B. solid boiling point
C. latent heat of solid
D. Evaporation
Answer» D. Evaporation
43.

Clothes keep us warm in winter because they . . . . .

A. provide heat
B. does not radiate heat
C. prevents air from coming in contact with the body
D. prevents body heat from leaving
Answer» E.
44.

What should be the minimum distance between the source of sound and the reflecting surface so that the sound can be heard clearly at

A. 10 meters
B. 17 meters
C. 24 meters
D. 30 meters
Answer» C. 24 meters
45.

What is the latent heat of vapor?

A. 536 Cal / g
B. 336 Cal / g
C. 542 Cal / g
D. 34℃ cal/g
Answer» B. 336 Cal / g
46.

The temperature of water at the bottom of a huge spring is higher than at the top because . . . . . .

A. Falling water absorbs the heat of the sun
B. bottom water has more potential energy
C. The kinetic energy of falling water is converted into
D. The heat is released from the rocks of the river bed
Answer» D. The heat is released from the rocks of the river bed
47.

What happens to the melting point of a pure substance when it is mixed with another substance?

A. rises up
B. happens to
C. remains unchanged
D. first increases then decreases
Answer» C. remains unchanged
48.

The hand burns more than the weight , because of the relatively boiling water . . .

A. steam has latent heat
B. steam enters the body
C. steam is lighter
D. Steam has more firepower
Answer» B. steam enters the body
49.

Thermocouple. . . . . . . . . . is made by?

A. two non-metals
B. two identical metals
C. two dissimilar metals
D. none of these
Answer» D. none of these
50.

If the door of the refrigerator kept in the room is left open. . . . . . .

A. The room will cool down to the temperature inside the refrigerator
B. The room will cool down to even temperature inside the refrigerator
C. the room will gradually warm up
D. The temperature of the air in the room will remain unchanged
Answer» D. The temperature of the air in the room will remain unchanged