Question

A ball of mass $0.5\, kg$ moving with a velocity of $2 \,ms ^{-1}$ strikes a wall normally and bounces back with the same speed. If the time of contact between the ball and wall is $10^{-3} s$, the average force exerted by the wall on the ball is

• A. 1125 N
• B. 1000 N
• C. 500 N
• D. 2000 N

Answer 1

Answer: (D)

2000 N

Answer 2

Impulse $=m v -(-m v)$ $=0.5 \times 2-(-0.5 \times 2)=2$ Hence, $F =\frac{2}{10^{-3}}=2000\, N$