A skydiver of mass $80 \mathrm{kg}$ falls $1000 \mathrm{m}$ from rest and then opens his parachute for the remaining $2000 \mathrm{m}$ of his fall. Air resistance is negligible until the parachute opens. The skydiver is travelling at $5 \mathrm{m}{ \mathrm{s}}^{-1}$ just before he hits the ground. Find the average resistance force when the skydiver is falling with the parachute open. (Use: $g=10 \mathrm{m} {\mathrm{s}}^{-2}$)

A golf ball of mass $45.9 \mathrm{g}$ is hit from a tee with speed $50{ \mathrm{ms}}^{-1}$. The ball lands in a pond that is $5 \mathrm{m}$ lower than the tee. When the ball lands in the pond it has travelled along a curved path of length $160 \mathrm{m}$. The resistance acting on the ball has magnitude $0.3 \mathrm{N}$.

Find the speed of the ball just before it hits the water.

The water immediately absorbs $8 \mathrm{J}$ of energy from the ball. The ball then sinks vertically downwards to reach the bottom of the pond. The resistance acting on the ball has magnitude $3 \mathrm{N}$ and the ball just comes to rest as it reaches the bottom of the pond.

A golf ball of mass $45.9 \mathrm{g}$ is hit from a tee with speed $50{ \mathrm{ms}}^{-1}$. The ball lands in a pond that is $5 \mathrm{m}$ lower than the tee. When the ball lands in the pond it has travelled along a curved path of length $160 \mathrm{m}$. The resistance acting on the ball has magnitude $0.3 \mathrm{N}$.

Find the depth of the pond.

A golf ball of mass $45.9 \mathrm{g}$ is hit from a tee with speed $180 \mathrm{km}{ \mathrm{h}}^{-1}$. The ball rises to a height of $20 \mathrm{m}$, having travelled along a curved path of length $61.875 \mathrm{m}$. At the highest point of its path the ball is travelling at $144 \mathrm{km}{ \mathrm{h}}^{-1}$.

Find the magnitude of the average resistance force acting on the golf ball.

The ball travels a further $105.8 \mathrm{m}$ along a curved path to land on the green. The green is $4 \mathrm{m}$ lower than the tee. The average resistance remains unchanged.

A golf ball of mass $45.9 \mathrm{g}$ is hit from a tee with speed $180 \mathrm{km}{ \mathrm{h}}^{-1}$. The ball rises to a height of $20 \mathrm{m}$, having travelled along a curved path of length $61.875 \mathrm{m}$. At the highest point of its path the ball is travelling at $144 \mathrm{km}{ \mathrm{h}}^{-1}$.

Find the speed of the ball just before it lands on the green.

The ball is travelling vertically when it lands on the green, where it is immediately brought to rest.

A golf ball of mass $45.9 \mathrm{g}$ is hit from a tee with speed $180 \mathrm{km}{ \mathrm{h}}^{-1}$. The ball rises to a height of $20 \mathrm{m}$, having travelled along a curved path of length $61.875 \mathrm{m}$. At the highest point of its path the ball is travelling at $144 \mathrm{km}{ \mathrm{h}}^{-1}$.

Show that the energy absorbed by the green is $28.1 \mathrm{J}$.