Question

What is an approximate value for the speed of sound in air?
(A) $30\,m{s^{ - 1}}$
(B) $300\,m{s^{ - 1}}$
(C) $30000\,m{s^{ - 1}}$
(D) $300000000\,m{s^{ - 1}}$

Answer 1

Hint: First let us see what is sound and how is the speed of sound affected-
Sound is a vibration that propagates through a transmitting medium such as a gas, liquid or solid as an acoustic wave. Often temperature is a factor that influences the speed of sound. Heat is a source of kinetic energy like sound. Molecules have more energy at higher temperatures. So they are able to vibrate faster. Because the molecules vibrate more rapidly, sound waves can move further.

Complete step by step answer:
Sound travelling is considered the transmission of sound.
The to and fro motion of the medium’s particles is how sound propagates.
The objects surrounding the medium vibrate as an object vibrates.
The particle in contact with the vibrating particle is displaced from its location of equilibrium first.The other particle in touch is disrupted by each particle. The disturbance is thus brought to the listener from the source. It is impossible for sound to travel in vacuum.
Sound waves have characteristics like-
1) Amplitude
2) Wavelength
3) Frequency
4)Time period
5) Velocity
Pitch of sound- It indicates shrillness or sound flatness. It depends on the vibrational frequency. The higher the sound wave frequency, the higher the sounds pitch would be and vice versa. Loudness of a sound- It is a per-second measure of the sound energy hitting the ear. It depends on the sound wave’s magnitude. Sound speed is the distance covered by a sound wave per unit of time as it propagates across an elastic medium. So, the speed of sound is commonly taken as $300\,m{s^{ - 1}}$.
Hence, option B is correct.

Note: In a perfect gas the speed of sound depends solely on its temperature and composition. In ordinary air, the velocity has a poor reliance on frequency and pressure, marginally deviating from ideal behaviour. So, the speed of sound may somewhat vary in different mediums.