Class 8 Practice – Level 2 – Set 2 – Sound

Total questions: 25

In which scenario will an echo be the most prominent?

In a densely populated forest

In a narrow, enclosed room

In an empty hall with hard walls

In a small carpeted bedroom

None

Why is sound heard more clearly at night than during the day?

Sound waves reflect more at night

Sound travels faster at night

The temperature difference causes sound to bend downwards

The air density decreases at night

None

Which characteristic of a sound wave determines its pitch?

Amplitude

Wavelength

Intensity

Frequency

None

In which medium would sound travel the slowest?

Water

Steel

Air

Vacuum

None

Why are ultrasonic waves used in medical imaging?

They travel slower, making images clearer

They cannot penetrate body tissues

They are absorbed by bones only

They can penetrate soft tissues and reflect back images

None

If the amplitude of a sound wave is reduced by half, how does it affect its loudness?

Loudness doubles

Loudness decreases by four times

Loudness remains the same

Loudness decreases by half

None

Why does sound travel faster in humid air than in dry air?

Humid air is warmer

Humid air has more oxygen

Water vapor in humid air is less dense than nitrogen or oxygen

Humid air has a greater density than dry air

None

Which sound frequency range is typically considered painful for the human ear?

0 - 20 Hz

Above 120 dB intensity regardless of frequency

300 - 3,000 Hz

20,000 - 100,000 Hz

None

Which component in a loudspeaker is responsible for amplifying sound?

Diaphragm

Magnet

Cone

Circuit board

None

10.

Why do theaters and auditoriums use curved walls or ceilings?

To create echoes

To focus sound towards the audience

To trap sound

To reduce sound speed

None

11.

What happens to the wavelength of a sound wave if the frequency increases in the same medium?

Wavelength decreases

Wavelength increases

Wavelength remains the same

Wavelength doubles

None

12.

Why does sound travel faster in solids than in gases?

Solids have a higher temperature

Solids are more compressible

Particles in solids are closer together

Solids have lower density

None

13.

Which of the following is within the audible range for most humans?

10 Hz

18,000 Hz

25,000 Hz

100,000 Hz

None

14.

How does ultrasound help in detecting fractures?

By creating echoes from bone surfaces

By vibrating bone cells

By amplifying sound waves in muscle

By measuring blood flow

None

15.

What happens to sound intensity when air pressure decreases?

Sound intensity increases

Sound intensity decreases

Sound speed doubles

Sound frequency changes

None

16.

Which device converts sound energy into electrical signals?

Loudspeaker

Microphone

Amplifier

Tuner

None

17.

Why are echoes not heard in small rooms?

Distance is insufficient for a distinct echo

Sound waves are absorbed completely

Sound speed is reduced in small spaces

Echoes require multiple reflections

None

18.

How does a change in frequency affect the pitch of a sound?

Higher frequency means lower pitch

Higher frequency means higher pitch

Frequency doesn’t affect pitch

Lower frequency increases amplitude

None

19.

What type of material is most effective for sound absorption in a recording studio?

Concrete

Glass

Metal

Fabric

None

20.

Why can humans not hear infrasound?

It has too high a frequency

It travels too slowly

It has a frequency below 20 Hz, outside the human hearing range

It is blocked by air

None

21.

What effect does increasing the amplitude of a sound wave have?

It increases loudness

It lowers pitch

It decreases speed

It changes frequency

None

22.

Why can sound travel great distances underwater compared to in the air?

Sound travels slower underwater

Sound waves are not absorbed as much underwater

Sound reflects completely at water surfaces

Water molecules block sound

None

23.

Which of the following can be a health effect of prolonged exposure to high noise levels?

Enhanced sleep quality

Decreased blood pressure

Increased stress and hearing loss

Improved concentration

None

24.

Which of these is an example of a natural source of sound?

Radio

Horn

Thunder

Loudspeaker

None

25.

Which characteristic of sound is mainly responsible for the formation of an echo?

Speed

Frequency

Reflection

Absorption

None

1 out of 25

Time's up

Class 8 Practice – Level 2 – Set 2 – Sound

Welcome back