An automobile is started from rest with one of its doors initially at right angles. lf the hinges of the door are toward the front of the car, the door will shut as the automobile picks up speed. The acceleration a is constant and the centre of mass is at a distance d from the hinges. The time
T needed for the doors to close is given by:
[Given:∫π20dθ√sinθ=N](Consider the door as a square plate)