In each of the following cases, state what provides the resultant force causing centripetal acceleration:

(a) the Moon orbiting the Earth

In each of the following cases, state what provides the resultant force causing centripetal acceleration:

A car going round a bend on a flat, rough road

In each of the following cases, state what provides the resultant force causing centripetal acceleration:

(c) the weight on the end of a swinging pendulum.

Calculate how long it would take a ball to orbit the Earth once, just above the surface, at a speed of $7920 \mathrm{m}{\mathrm{s}}^{-1}$. (The radius of the Earth is $6400 \mathrm{km}$.)

A stone of mass $0.20 \mathrm{kg}$ is whirled round on the end of a string in a vertical circle of radius $30 \mathrm{cm}$. The string will break when the tension in it exceeds $8.0 \mathrm{N}$. Calculate the maximum speed at which the stone can be whirled without the string breaking.

The International Space Station has a mass of $350$ Tonnes ad orbits the earth at an average height of $340 \mathrm{km}$ Where the gravitational acceleration is $8.8 {\mathrm{ms}}^{-2}$. The radius of the earth is $6400 \mathrm{km}$. Calculate the centripetal force on the space station.