A body undergoing SHM about the origin has its equation given by x = 0.2 cos 5πt. Find its average speed from t = 0 to t = 0.7 s
Physics · Simple Harmonic Motion
JEE Mains Advanced

Question

A body undergoing SHM about the origin has its equation given by x = 0.2 cos 5πt. Find its average speed from t = 0 to t = 0.7 s

G1 Physics · Accepted Answer

x=0.2 cos5πt gives T=2π/(5π)=0.4 s and speed maximum 1 m s⁻¹. In 0.7 s=1.75T the particle travels 4A in one cycle plus 3A in the next 0.75 cycle: distance=7A=1.4 m. Average speed=1.4/0.7=2 m s⁻¹.