Question

A rolling ball speeds up to 40 m/s with a rate of acceleration of 4m/s2. While speeding up the ball moves 120 meters. Approximately what was the ball's initial speed? a 18 m/s b 25 m/s c 52 m/s d 2 m/s

Answer 1

b. 25 m/s

Step-by-step explanation:

Given:

s = 120 m

v = 40 m/s

a = 4 m/s²

Find: u

v² = u² + 2as

(40 m/s)² = u² + 2 (4 m/s²) (120 m)

u = 25.3 m/s

The initial speed is approximately 25 m/s.