Two pendulums of time periods 3 s and 7 s , respectively start oscillating simultaneously from two opposite extreme positions. After how much time they will be in same phase?

Step-by-step solution

General equation of oscillation are aligned & y₁=A ( ₁ t+ 2 ) & y₂=A ( ₂ t+ 2 ) aligned Now, ₁ t+ 2 = ₂ t- 2 or aligned t & = ₂- ₁ & = (2 / T₂ )- (2 / T₁ ) & = T₁ T₂ 2 (T₁-T₂ ) & = 3 7 2(7-3) = 21 8 ~s aligned