
Every object in the universe attracts every other object with a force which is proportional to the product of their masses and inversely proportional to the square of the distance between them. The forces along the line joining the centre of the two objects.
❍ Let us consider two masses m1 and m2 line at a separation distance d. Let the force of attraction between the two objects be F.
According to universal law of gravitation,

Also,

Combining both, We will get

Or, We can write it as,

Where, G is the constant of proportionality and it is called 'Universal Gravitational constant'.
☯️ Hence, derived !!
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