Weight

DEFINITION:

“The weight of an object is the measurement of gravitational force acting on the object”.

OR

“The force with which Earth’s gravitational field pulls the object downwards is called ‘Weight’ ”.

EXPLANATION:

Weight $W$ of an object of mass $m$, in a gravitational field of strength $g$ is given by the relation:

$\boxed{W=mg}$

S.I UNIT:

Since, weight is a force therefore it’s S.I unit is also Newton($N$).

DIRECTION:

Weight is a vector quantity and for body on Earth it always directed towards the centre of Earth.

VARIATION ON EARTH:

The weight of the object changes as it moves away from the Earth, due to the variation of Earth's gravitational field strength at different places.

VARIATION ON DIFFERENT PLANETS:

The weight of the object is different at different planets. For example: Our body will have less weight at Moon because Moon's gravitational field is weaker than Earth.