Question

What is gravitational force ...

Answer 1

Gravitational Force

It states that every body in this universe attracts each other body with a force whose magnitude is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centres.

Consider two bodies of masses m1 and m2 with their centres mutually seperated by a distance r  

Let F be the force( in magnitude ) of gravitational attraction between two bodies.

So according to Newton's law of gravitation , m1 will apply force on m2 then m2 will also apply the same force on m1 only opposite in direction.

F will be directly proportional to m1. m2 - (1)

F will be inversely proportional to 1/ r2 - (2)

So from equation (1) and (2)

F is directly proportional to (m1. m2) /r2

so, Gravitational force, F = G .(m1.m2) /r2

Where G is constant of proportionality known as gravitational constant and also known as universal gravitational constant.

G = 6.67 x 10 -11 N m2 kg-2.

Gravitational force is always attractive in nature .

It is independent of medium between the particles.

It is always a conservative force.

The value of G doesn't depend on the nature and size of the masses.