State Newton's universal law of gravitation. Express it in mathematical form.

Explanation

Newton's universal law of gravitation: Every object in the Universe attracts every other object with a definite force. This force is directly proportional to the product of the masses of the two object s and inversely proportional to the square of the distance between them.
Mathematical form : Consider two objects of masses `m_(1)` and `m_(2)`. We assume that the objects are very small spheres of uniform density and the distance r between their centres is very large compared to the radii of the spheres.

The magnitude (F) of the gravitational force of attraction between the objects is directly proportional to `m_(1)m_(2)` and inversely proportional to `r^(2)`.
`therefore F prop (m_(1)m_(2))/(r^(2)) " " therefore F=G(m_(1)m_(2))/(r^(2))`
where G is the constant of proportionally , called the universal gravitational constant .