Question

A toy truck travels a distance of 2.5 meters in 0.95 seconds after a ball is shot out from it in the opposite direction. The mass of the truck is 1kg angmdthe ball is 0.06 kg. What is the velocity of the ball.

Answer 1

First, find the initial speed of the toy truck:

$$v=2d/t.$$

Next, according to conservation of momentum, we can write

$$Mv=mu, \\\space\\ u=\frac{Mv}{m}=\frac{2dM}{mt}=\frac{2\cdot2.5\cdot1}{0.06\cdot0.95}=87.7\text{ m/s}.$$