Question

A particle is performing simple harmonic mo-
tion having time period 3s is in phase with an-
other particle which is also undergoing simple
harmonic motion at t = 0. The time period
of second particle is T (less than 3s). If they
are again in the same phase for the third time
after 45s, then the value of T is
1) 2.8s 2) 2.75 3) 2.5s 4) 3.2s​

Answer 1

Answer:

Every 15 sec they are in phase

So the second must make 6 oscillations while the first makes 5 oscillations.

Then T = 5/6 * 3 = 2.5 sec