NTA Abhyas JEE Main2020PhysicsOscillationsPractice
What will be the time period of the pendulum of length l suspended from the ceiling of a cart which is sliding without friction on an inclined plane of inclination θ ?
Options
- A2 π l ⁡ g cos θ
- B2 π 3 l g cos θ
- C4 π 2 l ⁡ g cos θ
- D3 π 4 l 2g cos θ
Correct answer
A. 2 π l ⁡ g cos θ
Step-by-step solution
Here, point of suspension has an acceleration. a → = g sin θ (down the plane). Further, g → can be resolved into two components g sin θ (along the plane) and g cos θ (perpendicular to plane). g → eff = g → - a → = g cosθ (perpendicular to plane) T = 2 π l ⁡ | g → eff |   = 2 π l ⁡ g cos θ