Differences between Mass and Weight of a body

Weight and Mass are not the same physical quantity. They have different units and dimensions. However, they are related to each other. In this article, I’m going to explain how is weight different from Mass and how to get weight from the mass of an object.

Mass Measuring machine
Measuring the Mass

Differences between Mass and Weight

Here are some differences between these two physical quantities in tabular form –

SL. No.MassWeight
1It gives the amount of matter in an object.It gives the force exerted by a body due to its mass.
2Mass is a Scalar quantity.Weight is a vector quantity.
3It is a fundamental physical quantity.It is a compound physical quantity.
4SI unit of Mass is Kilogram (kg).SI unit of Weight is Newton (N).
How is the mass different from the weight?

How to get weight from mass?

There is an equation that relates the weight of an object with its mass. One can find the weight of a body from that equation when its mass is given. If m is the mass of an object and g is the acceleration due to gravity, then the equation of weight of the object is W = mg…………(1)

This equation is very much similar to the equation of force that Newton’s 2nd law of motion gives (F = ma). On the Earth’s surface, the value of g is 9.8 m/s2. Thus if a man has a mass of 50 kg on the Earth’s surface, then its weight on the Earth’s surface will be W = 50×9.8 = 490 Newtons. This is how one can calculate the weight from the mass.


  • Mass and Weight are two different physical quantities. Mass is one of the fundamental physical quantities.
  • If the mass of an object is given then its weight can be calculated by multiplying the mass by the gravitational acceleration.
  • Since the gravitational acceleration changes with height and also planet to planet, the weight of an object will not be the same always. But Mass will be the same everywhere.

This is all from this article on the relation and difference between mass and weight. If you have any doubts on this topic, ask me in the comment section.

Thank you!

Related Posts:

  1. Relation between Mass, Volume and Density