JEE Main202131 Aug 2021Evening ShiftPhysicsOscillationsActual
A bob of mass m suspended by a thread of length ℓ undergoes simple harmonic oscillations with time period T . If the bob is immersed in a liquid that has density 1 4 times that of the bob and the length of the thread is increased by 1 3 r d of the original length, then the time period of the simple harmonic oscillations will be:
Options
- A3 4 T
- B4 3 T
- CT
- D3 2 T
Correct answer
B. 4 3 T
Step-by-step solution
T = 2 π ℓ g g e f f = g - g 4 = 3 g 4    ∴   T ' = 2 π 4 ℓ / 3 3 g / 4 = 2 π 16 ℓ 9 g T ' = 4 3   T