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