Question

A metallic spoon falls on a metal plate making a huge sound and upon bouncing from the plate, it falls on to the pile of sand below it with no noise being heard. Sound is not heard on sand because
A. Sound is absorbed by sand particles
B. Sound generated by the plate is more than the sand particles
C. Vibration of metal plate is more than sand particles
D. Sand does not vibrate

Answer 1

Hint: To explain the solution of this problem, we must know the nature and behavior of metal and sand for transmitting the vibrations.

Complete step by step answer:
The vibration or oscillation is a type of motion that repeats itself after an interval of time. The examples of vibrations are swinging of a pendulum and the motion of a plucked string.
The study of oscillatory motions of bodies and the forces associated with them are studied under the theory of vibrations.

The vibrations are classified as; free and forced vibration, undamped and damped vibration, linear and nonlinear vibration, and deterministic and random vibration
In the vibration system, there is an alternate transfer of potential energy to kinetic energy and of kinetic energy to potential energy.

Vibration is involved in many human activities in one form or other which are as; we can hear because our eardrums vibrate, we can see because light waves undergo vibration, we can breathe because our lungs vibrates, walking involves (periodic) oscillatory motion of legs and hands, and human speech requires the oscillatory motion of tongues
In the metal, the atoms are closely packed that is the reason; the metal transferred the vibrations so well. In the sand, the particles are not so closely packed so it cannot transfer the vibrations so well.

Sound is not heard on sand because the vibration of metal plates is more than sand particles.

So, the correct answer is “Option C”.

Note:
The solution of this problem can also be given by explaining the concept of sound waves. We can hear things because sound waves generated from the source enter the outer ear and pass through the ear canal, which leads to the eardrum. After that the eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear.