Two pendulums have time periods T and 5 T / 4 . They start SHM at the same time from the mean position. What will be the phase difference between them after the bigger pendulum completed one oscillation?

Step-by-step solution

When bigger pendulum of time period 5 T 4 completes one vibration, the smaller pendulum will complete ( 5 4 ) vibrations. It means the smaller pendulum will be leaded the bigger pendulum by phase T 4 sec = 2 rad =90^ .