A simple pendulum performs simple harmonic motion about.x = 0 with an amplitude a and time period T. The speed of the pendulum at x = a2 will be
πa32T
πaT
3π2aT
πa3T
v = dydt = Aω cos ωt = Aω1-sin2ωt
= ωA2-y2
Here, y = a2
∴ v = ωa2-a24 = ω3a24 = 2πTa32 = πa3T