The force that pulls things to the ground on Earth (and other planets) is called gravity.
Gravity also holds Earth and the other planets in their orbits around the Sun.
Gravity is a very useful force – It keeps us on the Earth, and keeps the Earth and the other planets revolving around the Sun. It holds everything together, which is why it has been called ‘The Universal Glue’.
Although the force of gravity also exists on the Moon it is not as strong as it is here on Earth. This is because the Moon is much smaller than the Earth it is not as heavy as the Earth, and so gravity is much weaker there.
In the past people thought that heavier things fell faster than light things. Galileo, an Italian scientist from the 1600’s, conducted some experiments and found that things with different weight fell at approximately the same speed.
Below are the videos we looked at in class:
Another resource is:
Some extension links: