Answer: Option C. -> 0 ms−1
:
C
Sound wave is a mechanical wave which requires a medium for its propagation. It cannot travel through vacuum. Hence, the speed of sound is zero in vacuum.

Answer: Option D. -> solids, liquids and gases
:
D
A mechanical wave requires medium to propagate. Hence, itis not capable of transmitting its energy through vacuum.
A sound wave is an example of mechanical wave. It can propagate through all the three mediums solids, liquids and gases.However, it is incapable of travelling throughvacuum.

Answer: Option A. -> frequency
:
A
The frequency of a sound wave is expressed in hertz (Hz). Amplitude and wavelength are measured in metre(m). Time period is measured in second (s).

Answer: Option A. -> True
:
A
Very loud music causes discomfort and candamage theears. Hence, it can be considered as noise.

Answer: Option B. -> larynx
:
B
Vocal cords are present in the larynx. It is also called as voice box. Their vibration is responsible for the production of sound in humans.

Answer: Option B. -> Wave B has a lower pitch than wave A.
:
B and D
The pitch of a sound depends on its frequency. Higher the pitch, higher the frequency. Also, frequency is equal to the inverse of time period. So, if the time period of a wave is more, it means its frequency is less, and hence it also has a lower pitch. So, wave B has a lower pitch than wave A.
Loudness depends on the amplitude. Larger the amplitude, louder is the sound. So, wave B is louder than wave A.

Answer: Option D. -> solids, liquids and gases
:
D

A mechanical wave requires medium to propagate. Hence, it is not capable of transmitting its energy through vacuum.
A sound wave is an example of mechanical wave. It can propagate through all the three mediums solids, liquids and gases. However, it is incapable of travelling through vacuum.

Answer: Option A. -> $10$ Hz
:
A

Here, total number of oscillations = 10
Total time taken = 1 s
Hence, time taken for 1 oscillation = $\frac{1}{10}$ s
The time required to complete one oscillation is known as time period (T).
Now, frequency, $f=\frac{1}{T}$ = 10 Hz

Answer: Option A. -> frequency
:
A

The frequency of a sound wave is expressed in hertz (Hz). Amplitude and wavelength are measured in metre (m). Time period is measured in second (s).

Answer: Option C. -> $0m{s}^{-1}$
:
C
Sound wave is a mechanical wave which requires a medium for its propagation. It cannot travel through vacuum. Hence, the speed of sound is zero in vacuum.