Gravity is the name for a force that pulls everything down toward the centre of the Earth.
Gravity also pulls any object with mass toward each other. E.g. the Earth and the Moon or the Moon and the Sun.
Gravity is normally represented by an arrow on a object pointing downward.
For every 100 grams mass an object has, gravity pulls on it with a force of 1 Newton.
Gravity works the same in air or on the ground or in water.
The further you travel from the centre of the Earth the less effect gravity has. Becuase the Earth is spherical, it is the same everywhere on its surface. However if you were to go into space the force of gravity you feel would be less.
When you ‘escape gravity’ it means you are travelling fast enough to leave the surface of the Earth despite gravity pulling you back. This requires a very powerful rocket!
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