Question

4.a squash ball with an initial velocity of 25 m/s w is hit by a squash racket, changing its velocity to 30 m/s e in 0.25 s. what is the squash balls average acceleration?

Explanation:

Step1: Define variables and direction

Let east be the positive direction. Initial velocity \( v_i = -25 \, \text{m/s} \) (west is negative), final velocity \( v_f = 30 \, \text{m/s} \) (east is positive), time \( \Delta t = 0.25 \, \text{s} \).

Step2: Use acceleration formula

Acceleration \( a = \frac{\Delta v}{\Delta t}=\frac{v_f - v_i}{\Delta t} \)

Step3: Substitute values

\( a=\frac{30 - (-25)}{0.25}=\frac{55}{0.25} = 220 \, \text{m/s}^2 \) (direction is east as acceleration is positive)

Answer:

The squash ball's average acceleration is \( 220 \, \text{m/s}^2 \) [E]