Question

What are the essential properties a medium must possess for the propagation of mechanical waves?

• A. Stable pressure
• B. Maximum friction
• C. Constant temperature
• D. Minimum friction

Answer 1

The correct option is D

Minimum friction

Explanation of the correct option: -

Option D: Friction: -

1. The force preventing sliding against one another of solid surfaces, fluid layers, and material components is known as friction.
2. Friction can take many different forms. Out of which two solid surfaces in touch are opposed to one another's the relative lateral motion by dry friction.
3. Another essential property of a medium must be constant pressure in order for the propagation of mechanical waves.

Minimum Friction: -

1. To ensure that the medium's particles continue to oscillate for a sufficiently long period of time and that the wave travels through it for a sufficiently long distance, the friction force between them should be negligibly minimal.

Explanation of the incorrect options: -

Option A:- Stable pressure

1. If the environmental lapse rate is lower than the moist adiabatic lapse rate, the atmosphere is said to be absolutely stable.
2. This means that even when it reaches saturation, a rising air parcel will always cool more quickly than the surroundings.
3. Due to the cooling of the air parcel, if a mechanical wave passes through the air parcel, it loses its energy to propagate further.

Option B:- Maximum friction

1. The amount of force required to cause the object to move is represented by friction.
2. The object won't move if the applied force is equal to or less than friction.
3. The temperature effect the propagation of waves and the constant temperature does not cause any difference in presence of frictional force.
4. Hence, if the object cannot move it is not an ideal property for a mechanical wave to propagate.

Option C:- Constant temperature

1. Isothermal processes are described as ones that take place at a constant temperature. There are several isothermal processes that are often used.
2. At constant temperatures, the working fluid undergoes a change in phase during the boiling and condensing processes.
3. Hence, in this property, the medium through which the mechanical wave will propagate will undergo a change in phase which is not ideal for wave propagation.

So, Option (D) is correct. A medium must possess Minimum friction for the propagation of mechanical waves.