Q110
A body is said to be under forced vibrations, when
A.
There is a reduction in amplitude after every cycle of vibration
B.
No external force acts on a body, after giving it an initial displacement
C.
A body vibrates under the influence of external force
AnswerD.
None of the above
Answer: Option C
Solution
Answer: Option C
Solution:
Forced vibrations occur when a body is made to vibrate by the continuous action of an external periodic force.In this case, the vibration is maintained by the applied external force rather than by the body’s own natural tendency to vibrate.
Option A describes damped vibrations, where amplitude decreases after each cycle due to energy loss.
Option B refers to free vibrations, where no external force acts after the initial displacement.
Therefore, a body is said to be under forced vibrations when it vibrates under the influence of an external force, making Option C the correct answer.