A simple pendulum is set up in a trolley which moves to the right with an acceleration a on a horizontal plane. Then the thread of the pendulum in the mean position makes an angle `theta` with the vertical

Options

A. `"tan"^(-1)(a)/(g)` in the forward direction
B. `"tan"^(-1)(a)/(g)` in the backward direction
C. `"tan"^(-1)(g)/(a)` in the backward direction
D. `"tan"^(-1)(g)/(a)` in the forward direction

Answer

B

Explanation

In accelerted frame of reference a fictitious force (pseudo force) ma acts
on the bob of pendulum.
Hence, `tan theta = (ma)/(mg) = (a)/(g) rArr theta - tan^(-1) ((a)/(g))`
in the backward direction