Question

Find out time period of pendulum if it oscillates 120 times in a minute

Answer 1

120/60=2
1/2=0.5 is the time period

Answer 2

The number of oscillation per second is the frequency = 120/60 = 2 
Thus the pendulum makes 2 oscillation per second
We know that time period = 1/frequency 
Therefore, the time period of the pendulum = 1/2 = 0.5 seconds

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