Question

what is the time period of simple pendulum if it completes 20 oscillations in 15 seconds ? Pls do all numerical with formula

Answer 1

so the time period is 0.75seconds

Answer 2

No. of oscillations completed by the pendulum= 42 

Time taken to complete 42 oscillation= 20 seconds 

Time period= No. of oscillations completed/Time taken 

Time period= 42/20 

= 21/10 (cancelled by 2) 

= 2.1 

Time period= 2.1 seconds