The diagram in Fig. 7.12 shows the displacement – time graph of vibr

1.	The diagram in Fig. 7.12 shows the displacement – time graph of vibrating body.(i) name the kind of vibrations(ii) Give one example of such vibrations(iii) why is the amplitude of vibrations gradually decreasing?(iv) what happens to the vibrations of the body after some time?
Answer» (i) Damped vibrations (ii) Example: When a slim branch of a tree is pulled and then released, it makes damped vibrations. (iii) The amplitude of vibrations gradually decreases due to the frictional (or resistive) force which the surrounding medium exerts on the body vibrating in it. As a result, the vibrating body continuously loses energy in doing work against the force of friction causing a decrease in its amplitude. (iv) After sometime, the vibrating body loses all of its energy and stops vibrating.

The diagram in Fig. 7.12 shows the displacement – time graph of vibrating body.(i) name the kind of vibrations(ii) Give one example of such vibrations(iii) why is the amplitude of vibrations gradually decreasing?(iv) what happens to the vibrations of the body after some time?

Answer»

(i) Damped vibrations

(ii) Example: When a slim branch of a tree is pulled and then released, it makes damped vibrations.

(iii) The amplitude of vibrations gradually decreases due to the frictional (or resistive) force which the surrounding medium exerts on the body vibrating in it. As a result, the vibrating body continuously loses energy in doing work against the force of friction causing a decrease in its amplitude.

(iv) After sometime, the vibrating body loses all of its energy and stops vibrating.

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