Question

A 7 kg ball is moving at a constant speed of 5 m/s. A force of 300 N is applied to the ball for 4 s. The new speed of the ball is ?

Answer 1

The new speed of the ball is 176.43 m/s

Step-by-step explanation:

Given;

mass of the ball, m = 7 kg

initial speed of the ball, u = 5 m/s

applied force, F = 300 N

time of force action on the ball, t = 4 s

Apply Newton's second law of motion;

`F = ma = (m(v-u))/(t)\\\\m(v-u) = Ft\\\\v-u = (Ft)/(m)\\\\v = (Ft)/(m) + u`

where;

v is new speed of the ball

`v = (Ft)/(m) + u\\\\v =(300*4)/(7) + 5\\\\v = 176.43 \ m/s`

Therefore, the new speed of the ball is 176.43 m/s