Question

A ball of mass 0.05 kg strikes a smooth wall normally four times in 2 second with a velocity of 10m/s. Each time the ball rebounds with the same speeds of 10m/s. Calculate the average force on the wall

Answer 1

Answer" The average force on the wall be equal to 0.5 N.

Explanation:

To calculate the average force on the wall, we use the following equation:

$Ft=m\Delta v\\\\F=\frac{m(v_2-v_1)}{t}$

where,

F = average force = ?N

m = mass of the ball = 0.05kg

$v_1$ = Initial velocity of the ball = -10m/s (negative sign because the ball rebounds)

$v_2$ = Final velocity of the ball = 10m/s

t = time taken by the ball = 2s

Putting values in above equation, we get:

$F=\frac{0.05kg[10-(-10)]m/s}{2s}\\\\F=\frac{0.05kg(20m/s)}{2s}\\\\F=0.5kgm/s^2=0.5N$

Hence, the average force on the wall will be equal to 0.5N.