Calculate the speed $u$.
State how Newton’s third law is shown in the collision between the ball and the ground.
The ball is in contact with the ground for $0.091\,\text{s}$. It rebounds vertically and leaves the ground at a speed of $5.4\,\text{m s}^{-1}$. The ball has a mass of $0.059\,\text{kg}$. Calculate the magnitude of the change in momentum of the ball during the collision.
Determine the magnitude of the average resultant force acting on the ball during the collision.
Use your answer in (c)(ii) to calculate the magnitude of the average force exerted by the ground on the ball during the collision.
The ball was thrown downward at time $t = 0$ and reaches the ground at time $t = T$. On Fig. 2.2, sketch a graph to show how the speed of the ball varies with time $t$ from $t = 0$ to $t = T$. Numerical values are not needed.
In practice, air resistance is not negligible. State and explain the variation, if any, with time $t$ of the gradient of the graph in (d) when air resistance is not negligible.