Weight of a body is the force of gravity on the body. or The gravitational force acting on a body.


Is the force a body exerts on anything which freely supports it in the gravitational field.

Weight of body = mass of body “m” (kg) x acceleration due to gravity, g. W = mg

The S.I unit of weight is a newton “N” Weight of a body varies from place to place or from planet to planet.

Why weight of a body varies

Weight of a body varies because of the following reasons:

i) The shape of the earth is not a perfect sphere. so at the equator the value of acceleration due to gravity is less than that at the pole. This makes the weight of the body to be less at the equator and greater at the poles.

ii) Planets have different accelerations due to gravity. A body resting on the surface experience a reaction force R from the surface which supports it.

image 174

Differences between Mass and weight

image 175