Question

A ball with mass m and speed $V_0$ hit a wall and rebounds back with same speed.
Calculate the change in the object's kinetic energy.

• A. $-m{v}_0^2$
• B. $-\frac{1}{2}m{v}_0^2$
• C. Zero
• D. $\frac{1}{2}m{v}_0^2$
• E. $m{v}_0^2$

Answer 1

Answer: (C)

Zero

The speed of the ball remains the same $v_0$ before and after the collision with wall.

Thus the kinetic energy remains $\frac{1}{2}m{v}_0^2$.

Since kinetic energy is a scalar quantity, the change in it is zero.