Two simple pendulum of length #l# and #16l# are released from the same phase together. They will be at the same phase after a minimum time?
The time in which smaller pendulum will complete 4 oscillations or in which larger will complete 1 oscillation
If T1 be the time period of pendulum 1 and T2 that of the 2nd one,
We can say
That means 4 oscillations of T1 is completed in the same time in which 1 oscillation of T2 is completed . Hence after that time thay will again be in the same phase.