Speed of Sound

Q.

A polyatomic ideal gas has $24$ vibrational modes. What is the value of $\mathrm{\gamma }$?

1. $1.03$

2. $1.30$

3. $10.3$

4. $1.37$

Q.

The speed of sound in air decreases with the increase in the humidity of air.

1. True

2. False

Q.

Calculate the wavelength of a sound wave whose frequency is $220\mathrm{Hz}$ and speed is $440\mathrm{m}/\mathrm{s}$ in a given medium

Q.

What are the conditions for constructive and destructive interference?

Q. What is meant by propagation?

Q.

During the night, distant sounds become louder than during the day. This is due to:

1. Reflection of sound waves.

2. Refraction of sound waves.

3. Absence of other sounds.

4. Echo of the sounds.

Q.

Sound can travel through

1. Gases only

2. Solids-only

3. Liquids only

4. solids, liquids and gases only

Q.

Write the relationship between velocity, wavelength and time period of a wave.

Q.

What is a free vibration?

Q. Question 3
Suppose you and your friend are on the moon. Will you be able to hear any sound produced by your friend?

Q.

Explain the wave parameters in details.

Q.

If the time interval between lightning and thunder is 2 seconds, what is the distance of the point of the lightning ? ( Speed of sound in air is 346 ms^-1 )

Q.

What is meant by supersonic speed?

Q.

For a wave propagating in a medium, identify the property that is independent of the others

1. Frequency

2. Velocity

3. Wavelength

4. All the above options

Q.

A sound wave strikes a high wall perpendicularly. What is the angle of incidence for the sound wave?

1. 0

2. 90

3. 40

4. 60

Q.

If you place your ear close to an iron railing which is tapped some distance away, you hear the sound twice. Explain why ?

Q.

Velocity of sound in air is about

1. 330 m/s

2. 360 m/s

3. 380 m/s

4. 400 m/s

Q.

What is natural frequency formula?

Q. In gases a sound wave is ______________.

1. transverse
2. lateral
3. longitudinal
4. both longitudinal and transverse

Q. Does the frequency of sound wave changes with the medium

Q.

A source of wave produces 40 crests and 40 troughs in 0.4s. What is the frequency of the wave?

Q.

In which of the following medium speed of the sound is maximum?

1. Steel

2. Wood

3. Water

4. Air

5. Helium

Q.

Which of the following is the speed of sound in copper and which in aluminium ?

(a) 5100 m/s

(b) 1500 m/s

(c) 3750 m/s

Q.

Calculate the wavelength of a sound wave whose frequency is $200Hz$ and speed is $440m/s$ in a given medium.

Q.

What are good and bad reflectors of sound? Give two examples each.

Q. Why does sound gets reflected from wall, other than getting absorbed by the wall and keeping the propagation going on

Q.

What are good and bad reflectors of sound?

Q.

The time interval between a lightning flash and the first sound of thunder is 5 s. If the speed of sound in air is 330 m $s^{-1}$, find the distance of flash from the observer.

Q.

State the laws of reflection of sound.

Q.

What is the speed of sound :

(a) in air ?

(b) in water ?

(c) in iron ?