Displacement time graph of a particle moving in a straight line is as shown in figure. Select the correct alternative (s) :
.

Options

A. Work done by all the forces in region `OA` and `BC` is positive
B. Work done by all the forces in region `AB` is zero
C. Work done by the forces in region `BC` is negative
D. Work done by all the forces in region `OA` is negative.

Answer

B

Explanation

In region `OA` particle is acceleratedin region `AB` particle has uniform velocity while in region `BD` particle is deceleration, Therefore, work done is positive in region `OA`, zero in region `AB` and negative in region `BC`.