Q. Calculate the time period of a simple pendulum of length suspended from the roof of a vehicle which moves without friction down an inclined plane of inclination angle .

 238  155 NTA AbhyasNTA Abhyas 2020 Report Error

Solution:

See the following force diagram.

Solution
Vehicle is moving down the frictionless inclined surface so, its acceleration is . Since vehicle is accelerating, a pseudo force will act on bob of pendulum which cancel the component of weight of the bob.
Hence net force on the bob is or net acceleration of the bob is
Time period