Question

What is the relation between 'time-period' and 'frequency' of an oscillating body?

Answer 1

TIme period (T) is the amount of time an oscillating body takes to repeat itself, and Frequency (f or $\nu$) is the number of times it repeats in one second or unit time.
If you measure time in s (seconds) then frequency is measured in Hz (cycles or periods per second).

Frequency is inversely proportional to the time period. i.e, $f=\frac{1}{T}$.