Question

Calling all benefactors, stars and other awesome people.

Everything important with proper explanation in chapter Gravitation of class 9. (50 points)

Answer 1

Hey

Gravitational force between two bodies is directly proportional to the product of the masses of the two bodies and is inversely proportional to the square of distance between them.

F directly proportional to M1M2/r²
(where M1 and M2 are the masses of the two bodies and r is the distance between the two bodies).

But F = G. M1. M2 / r²

here G is the gravitational constant with a value of 6.67 * 10^-11 m³/kg/s².

Hope it helps!!

Answer 2

                                 gravitation
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explanation of all concepts related to gravitation isn't easy.i will try to give better way for understand this chapter.

* according to NEWTON'S law of gravitation every particle in the universe attracts every other particle with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
  i.e.          F = GM₁M₂/r²
    where G is called gravitational constant and also known as universal constant having the value 6.67×10⁻¹¹ N-m²/Kg²

(a) it is always attractive.
(b) it is independent of the medium between the particles.
(c) it is a conservative force. i.e. work done by its path independent or work is done in moving a closed path under the action of gravitational force is zero.
(d) it holds good over a wide range of distance. it is found true for interatomic distances.
(e) it is an action-reaction pair. i.e. the force with which one body attract the second body is equal to the force with which moon attracts with earth.
(f) it is a central force.i.e.  acts along the line joining the centres of two intersecting bodies.
(g) it is two body interaction. 
(h) G is gravitational constant. it doesn't change in intervening medium or temperature or pressure.