There is an equation that links mass to weight in a gravitational field:

On Earth g = 10N/kg. Therefore my weight is 650 Newtons.

This is only true whilst I stay on Earth. On the moon, I would be very light and jumping would be very easy. This is because g (Moon) is only 1.67 N/kg. I would weigh a sixth of what I did on Earth, but it wouldn't mean I was any thinner.. I'd still have all those atoms and molecules that make up my mass!

Click here to read Hannah's 'Mass and Weight Rap'

Weight always acts vertically downwards on the Earth's surface

Earth's gravity is pulling the mass towards its centre with the force of its weight

The weight of an object is distributed evenly around a point on the body called its 'centre of gravity'. The weight is said to 'act through the centre of gravity'. If you support it at this point it will balance. You can find this point on a flat shape by carrying out a simple experiment.

The weight of a body can be represented by a force arrow that points vertically down from the centre of mass. The arrow shaft is the line of action of the force arrow.

If the object is positioned on a sloping surface we have to resolve the weight vector to find the force pulling it down the slopw and the reaction force with the ground. You will not have to do this until A Level.