Amplitude

Q. Define the following terms:

Q. The distance between two consecutive crests or troughs is called of the wave.

1. amplitude
2. wavelegth
3. frequency

Q.

Define loudness.

Q.

If the amplitude of sound wave is doubled then the loudness will become:

1. 2 times

2. 4 times

3. Half the initial value

4. None of these

Q.

Difference between forced vibrations and resonance.

Q.

Explain the following:

Why are the soldiers instructed to march out of step while crossing a bridge?

Q.

A source is producing 15 waves in 3 seconds. The distance between a crest and t
trough is 10 cm. Find the velocity of the wave?

Q.

State three factors affecting the loudness of a sound by a listener.

Q.

We can distinguish a shrill sound from a flat sound by its

1. amplitude

2. loudness

3. pitch

4. none of the above

Q. If a sound wave travels from east to west, then particles of medium move in the direction of.

1. east to west
2. south to north
3. north to south

Q. A pendulum is oscillating about its mean position(B) as shown in the following figure. A and C are the extreme positions of the pendulum during its to and fro motion. The displacement of the pendulum from the position B to the position C, or A, is called ______.

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

Q. Two sound waves - A and B are travelling in air. If the wave A has a time period of 2 s and an amplitude of 3 cm, and the wave B has a time period of 3 s and an amplitude of 11 cm, which of the following statements are correct?

1. Wave A is louder than wave B.
2. Wave B has a lower pitch than wave A.
3. Wave A has a lower pitch than wave B.
4. Wave B is louder than wave A.

Q.

Loudness of sound is directly proportional to cube of ampltude.

1. True

2. False

Q.

On which parameter does the loudness of sound depends?

Q.

State four characteristics of forced vibrations.

Q. The maximum displacement of a particle in vibratory motion about its mean position is called:

1. frequency
2. amplitude
3. wavelength
4. time period

Q. Q)The laws of reflection or refraction are the same for sound as for light . The index of refraction of a medium (for sound) is defined as the ratio of the speed of sound in air 343 m/s to the speed of sound in the medium. a) what is the critical angle θ for total reflection from water(v=1498)

Q. In longitudinal waves, the particle motion is perpendicular to the wave propagation.

1. True
2. False

Q. A mechanical wave needs a medium for its propagation.

1. True
2. False

Q.

The time period of a vibrating body is $0.02s$. The frequency of waves it emits is :

1. $5Hz$

2. $20Hz$

3. $200Hz$

4. $50Hz$

Q.

The ____ of a sound wave is expressed in hertz (Hz).

1. frequency

2. time period
3. wavelength

4. amplitude

Q. Waves that require a medium to propagate are known as mechanical waves.

1. True
2. False

Q. One vibration of a body takes 0.05 s. Determine its frequency.​

1. 0.2 Hz
2. 0.5 Hz
3. 20 Hz
4. 50 Hz

Q.

The number of vibrations per minute by an object is called loudness.

1. True
2. False

Q. The intensity of sound is independent of

1. the distance of source from the observer.
2. the amplitude of the sound.
3. the wavelength of the sound.
4. the maximum displacement of a particle from its mean position.

Q. A key of a mechanical piano is first struck gently, and then harder. Which properties of the sound produced would remain unchanged?

1. Amplitude
2. Frequency
3. Pitch
4. Intensity

Q.

Define Amplitude. [1 MARK]

Q. Why are the stringed instruments like guitar provide with a hollow sound box ?

Q. 64. The sound intensity level at a point 4m from the point source is 10db then the sound level at a distance 2m from the same source will be

Q. The maximum displacement of a particle from its mean position is called ___.

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