Question

Why there is gravitational force between any two bodies?

Answer 1

The Universal Gravitation Equation is:

F = GMm/R²

where

• F is the force of attraction between two objects in newtons (N)
• G is the Universal Gravitational Constant = 6.674*10⁻¹¹ N-m²/kg²
• M and m are the masses of the two objects in kilograms (kg)
• R is the separation in meters (m) between the objects, as measured from their centers of mass

But your question is how this gravitaional force is formed.
According to Newton's theory of gravitation, gravitational field comes from the mass. Magnetic force comes from magnetic particles.Electric force comes from charged particles.These charges produce magnetic field and electric field respectively. And if any other charge comes within the influence of these field, they feel force being exerted on them.
In the same way, you can consider mass as special kind of "charge" which is also an intrinsic property. Any particle having mass will produce gravitational field and if any other massive particle comes within the influence of this field it will feel a gravitational force being exerted on it.



This theory is according to classical physics. But a more defined explanation can be given by modern physics. But it would be difficult to understand and cannot be explained briefly. You will learn in higher classes about it