Question

A body is executing simple harmonic motion with an angular frequency 2rad/s. The velocity of the body at 20 mm displacement, when the amplitude of motion is 60 mm, is

[CPMT 1999]

• A. 40 mm/s
• B. 60 mm/s
• C. 113 mm/s
• D. 120 mm/s

Answer 1

The correct option is C

113 mm/s

v = $\omega \sqrt{(a^2-y^2)}=2\sqrt{{60}^2-{20}^2}$ = 113 mm/s.