Reflection of sound

Q.

Sound and light waves:

1. have similar wavelength

2. obey the laws of reflection

3. travel as longitudinal waves

4. travel through vacuum

Q. State true or false.
The angle of reflection equals to the angle of incidence, only holds true for the light wave but not for a sound wave.

1. False
2. True

Q. In a big hall, the sound gets reflected inside the hall multiple times.This phenomenon can be observed in:

1. Auditoriums
2. Cinema halls
3. Indoor stadiums
4. Vacuum chamber

Q.

Propagation of sound waves follow the laws of reflection.

1. Yes

2. No

3. Depends on the medium

4. Depends on the source

Q. Bats produce high-pitched ultrasonic squeaks. This allows a bat to locate how far it's prey is.

1. True
2. False

Q.

If a person drops a pebble in a well of $100m$ depth, after how much time (in seconds) will he be able to hear the sound?
Given:
Acceleration due to gravity, $g=10m{s}^{-2}$
Speed of sound in air, $v=343m{s}^{-1}$

1. $20s$

2. $\sqrt{20}+0.3s$

3. $\sqrt{20}s$

4. $0.3s$

Q.

For a sound wave, the reflected wave, incident wave and the normal to the reflecting surface always lie ___.

1. in different planes

2. in the same plane

3. in planes perpendicular to each other

4. incident and reflected waves are in the same plane while normal is in a perpendicular plane

Q.

What frequency do whales communicate at ?

1. Ultrasonic frequencies as high as 45 kHz

2. Infrasonic frequencies as low as 16 Hz

3. In the audible range of the human ear

4. Both A and B

Q. Ultrasound can be used for which of the following purposes?

1. Echocardiography
2. Ultrasonography
3. MRI scan
4. Loudspeakers

Q. Compression is a region of:

1. no pressure
2. high pressure
3. high frequency
4. low pressure