Define the terms:
$(i)$ vibration
$(ii)$ time period
$(iii)$ frequency and
$(iv)$ amplitude. [one mark each]

(N/A) $(i)$ One complete to and fro motion of a body is called one vibration.
$(ii)$ The time taken by a vibrating body to complete one vibration is called its time period.
$(iii)$ The number of complete vibrations that the vibrating body makes in one second is called its frequency.
$(iv)$ The maximum displacement of a vibrating body from its mean position is called its amplitude.