Question

Differentiate between:

1. Mass and weight

2. Universal gravitational constant and gravitational acceleration of earth

Answer 1

Sr. No.	Mass	Weight
I.	Mass is the quantity of matter contained in the body.	Weight is the force of gravity acting on the body.
II.	Mass is the measure of inertia of the body.	Weight is the measure of gravity.
III.	Mass is a constant quantity.	Weight is not a constant quantity. It is different at different places.
IV.	Mass has only magnitude.	Weight has magnitude as well as direction.
V.	SI unit of mass is kilogram (kg).	SI unit of weight is newton (N).

(2) Difference between universal gravitational constant and gravitational acceleration of the Earth:

Sr. No.	Universal gravitational constant	Gravitational acceleration of the Earth
I	Universal gravitational constant is defined as the force of attraction acting between two bodies each of unit mass, whose centers are placed unit distance apart.	Gravitational acceleration of Earth is defined as the constant acceleration produced in a body when it falls freely under the effect of gravity.
II	The value of universal gravitational constant is same throughout the universe.	The value of the gravitational acceleration of Earth changes from place to place.
III	The value of universal gravitational constant is 6.673 × 10–11 Nm2/kg2.	The value of the gravitational acceleration of Earth depends on the height or depth from the Earth’s surface. On the surface of the Earth, its value is 9.81m/s2.
IV	Universal gravitational constant is denoted by ‘G’.	Gravitational acceleration of Earth is denoted by ‘g’.