What is Frequency?

Frequency is the number of cycles per unit time. It is denoted by "f" and measured in Hertz. The reciprocal of frequency is Time Period, which is denoted by "T".

f=n/T
for example

Q: If there are 20 cycles of a wave within 4 seconds then what is the frequency?
Sol: Here, n= 20 and T =4 so

                 f=20/4
                 f=5Hz.