**Answer: Mass: **The amount of matter present in the object is Mass, a scalar quantity with SI unit kg. Its value is the same everywhere and does not change even when we go to another planet. According to Newton’s first law, it is the measure of the inertia of an Object. The higher the mass, higher is the inertia.

**Weight: **The weight of an object, on the other hand is the force with which the earth attracts the object. The force (F) on an object of mass m on the surface of the earth can be written using equation (4)

Weight (W) = F = m g …. ( g= GM/R^{2})

Since, Weight is a force, it is a vector quantity with the SI unit Newton and its direction is towards the centre of the earth. Given that the value of g is not the same everywhere, the weight of an object changes from place to place, even if its mass is constant everywhere. From this, it is seen that while the weight of an object on Earth and Mars may differ, its mass remains constant on Mars as well on Earth.