Weight, Mass and Gravity

Gravitational Force

• Gravity attracts all masses, but you only notice it when one of the masses is really big, e.g. a planet. Anything near a planet or star is attracted to it very strongly.
• This has two effects: on the surface of a planet, it makes all things fall to the ground, and gives everything a weight.

Weight and Mass

• Mass is the amount of stuff in an object. For any given object this will have the same value anywhere in the universe.
• Weight is the force acting on an object due to gravity (the pull of the gravitational force on the object). Close to the Earth, this force is caused by the gravitational field around the Earth.
• Gravitational field strength varies with location. It's stronger the closer you are to the mass causing the field, and stronger for larger masses.
• The weight of an object depends on the strength of the gravitational field at the location of the…