JEE Main202127 Jul 2021Evening ShiftPhysicsOscillationsActual
An object of mass 0 . 5 kg is executing simple harmonic motion. It amplitude is 5 cm and time period (T) is 0 . 2 s . What will be the potential energy of the object at an instant t = T 4 s starting from mean position. Assume that the initial phase of the oscillation is zero.
Options
- A0 . 62   J
- B6 . 2 × 10 - 3   J
- C1 . 2 × 10 3   J
- D6 . 2 × 10 3   J
Correct answer
A. 0 . 62   J
Step-by-step solution
T = 2 π m k 0 . 2 = 2 π 0 . 5 k k = 50 π 2 ≈ 500 x = A sin ( ω t + ϕ ) = 5   cmsin ω T 4 + 0 = 5   cmsin π 2 = 5   cm PE = 1 2 kx 2 = 1 2 ( 500 ) 5 100 2 = 0 . 6255