Loudness

Q. A source of sound emits $200\pi$ W power which is uniformly distributed over a sphere of radius $10m$. What is the loudness of sound on the surface of the sphere?

1. 107 dB
2. 80 dB
3. 117 dB
4. 70 dB

Q.

What is damped free vibration?

Q. Loudness is determined by the ________ of vibration.

1. 
   pitch
2. 
   intensity
3. 
   amplitude
4. 
   frequency

Q.

Loudness of a sound is directly proportional to the square of:

1. Amplitude

2. Frequency

3. None of these

4. Both Frequency and Amplitude

Q.

The human ear is most sensitive to which range of frequencies?

Q. The unit for measuring intensity of sound is _________ .

1. 
   decibel
2. 
   hertz
3. 
   second
4. 
   metre

Q.

The amplitude of a sound wave determines its:

1. Loudness

2. Pitch

3. Quality

4. Timbre

Q. If pressure of air is doubled then what is effect on speed of sound?

Q.

The sound level which is comfortable for the human ear is about ______ to ______ decibels.

Q.

Loudness of sound increases with

1. The amplitude of vibrating body

2. The increase in surface area of vibrating body

3. The decrease in frequency of vibrating body

4. The increase in distance from the source of sound

Q.

A vibrating tuning fork is placed over the mouth of a burette filled with water. The tap of the burette is opened and the water level gradually starts falling. It is found that the sound from the tuning fork becomes very loud for a particular length of the water column.
(i) Name the phenomenon taking place when this happens.
(ii) Why does the sound become very loud for this length of the water column?

Q. Question 23
An alarm bell is kept inside a vessel as shown in Fig. 13.1. A person standing close to it can distinctly hear the sound of alarm. Now if the air inside the vessel is removed completely how will the loudness of alarm get affected for the same person?

Q.

Quality Of Sound Primarily Depends Upon ______

1. Intensity

2. Wave Form

3. Frequency

4. Shape Of The Source

Q. the difference of sound level between two points is 30dB . the pressure amplitude between the poiints is

Q.

Which characteristics of the sound help you to identify your friend by his voice while sitting with others in a dark room?

Q. The pitch of the note depends upon the:

1. Tension on the drum surface
2. Diameter of the wind hole
3. Diameter of the drum surface
4. Tension on the string

Q. Define Amplitude and loudness of a sound wave. What is pitch of a sound?

Q.

What is the difference between note and tone?

Q.

The loudness of sound is to be increased to 4 times the initial value. By what factor must the amplitude be increased?

1. 16

2. 8

3. 2

4. 4

Q.

Due to a point isotropic sonic source, loudness at a point is L = 60 dB. If density of air is $\rho =\left(\frac{15}{11}\right)kg/m^3$ and velocity of sound in air is v = 330 m/s, the pressure oscillation amplitude at the point of observation is $[I_0={10}^{-12}W/m^2]$

1. 
2. 
3. 
4. 

Q.

Do radio waves require a medium for their propagation?

Q.

What is the relation between Loudness and Amplitude. [2 MARKS]

Q. How can a guitar produce sounds of different frequencies?

Q.

Two waves of the same pitch have amplitudes in the ratio 1:4, calculate the ratio of their loudness.

1. 2:1

2. 16:1

3. 1:16

4. 1:2

Q.

What is the function of a sound amplifier in a broadcasting unit?

Q.

Two waves have the frequencies 128 Hz and 256 Hz with same amplitude, then their loudness is in the ratio?

1. 2:1

2. 1:4

3. 1:1

4. 1:2

Q. The intensity of the sound near total silence is:

1. 4 dB
2. 0 dB
3. 3 dB
4. 1 dB

Q.

In wind instruments, pitch of sound increases when length of air column is ______________

Q.

Give one example of when electric energy changes into sound energy.

Q.

The amplitude of the sound waves determines the ___ of the sound.

1. pitch

2. loudness

3. quality

4. timber