Figure shows four situations in which a force is applied to a block. In all four cases, the force has the same magnitude, and the displacement of the block is to the right and of the same magnitude. Which of the following cases work done by the applied force on the block zero?

Options

A. (i)
B. (ii)
C. (iii)
D. (iv)

Answer

A

Explanation

Work done by the applied force is zero in (i) because in case (i) both the force and displacement are mutually perpendicular.