Question

The sound waves in gas are always
1. Transverse
2. Longitudinal
3. Polarized
4. Electromagnetic

Answer 1

Correct Answer - Option 2 : Longitudinal

CONCEPT:

• Waves: It is defined as a disturbance or variation that transfers energy progressively from point to point in a medium and that may take the form of elastic deformation or of a variation of pressure, electric or magnetic intensity, electric potential, or temperature.
  • ​There are two types of waves:
    1. Transverse wave: Waves in which the medium moves at right angles to the direction of the wave.
    2. Longitudinal wave: A longitudinal wave has the movement of the particles in the medium in the same dimension as the direction of movement of the wave.
• Sound: It is a vibration that propagates through a medium in the form of a mechanical wave.
  • The medium in which it propagates can either be a solid, a liquid, or a gas.
  • Sound travels fastest in solids, relatively slower in liquids, and slowest in gases.
  • The wave produces by the sound is called a sound wave
  • A sound wave is longitudinal in nature

The formula for the speed of sound (c):

c = D/t

Where d is the distance traveled by sound, t is the time taken to cover the distance.

EXPLANATION:

• Longitudinal waves travel in an elastic medium in form of compression and rarefaction which changes its volume, elasticity, and pressure

• Since air is a completely elastic medium, that is, it does not have a modulus of rigidity, therefore sound waves in the gas are longitudinal.

The correct option is 2.