Question

A racquetball strikes a wall with a speed of 30 m/s and rebounds with a speed of 26 m/s. The collision takes 20 ms. What is the average acceleration of the ball during collision?

a. zero
b. 1500 m/s2
c. 1300 m/s2
d. 200 m/s2
e. 2800 m/s2

Answer 1

e. 2800 m/s²

Step-by-step explanation:

Acceleration: This is the rate of change of velocity. The S.I unit of acceleration is m/s²

Applying Newton's equation of motion,

a = (v-u)/t ................................... Equation 1

Where a = acceleration, v = Final velocity, u = Initial velocity, t = time.

Note: Let the direction of the initial velocity be negative, and the direction of the final velocity be positive

Given: v = 26 m/s, u = -30 m/s, t = 20 ms = 0.02 s

Substitute into equation 1

a = [26-(-30)]/0.02

a = (26+30)/0.02

a = 56/0.02

a = 2800 m/s².

Hence the right option is e. 2800 m/s²