Question

Why a body with some mass attracts another object with mass with a force...

Answer 1

actually it is a universal law which cannot be proved.

Answer 2

Hey ........

Here is your answer......

Mass actually is a transformation of energy into elemental particles and then atoms. And, these atoms have mass due to which they attract. But, Why is it so?
We know that there are four forces in our universe -
All of these are responsible for attraction of one massive body to every other but, up to some extent they can be neglected.
Lets take nuclear force, strongest of all forces in nature. The gluons that are responsible for out breaking the repulsion between protons and leading to place all the protons and neutrons together in the nuclei of an atom. But, even being the strongest of all its range is too small. So, it somehow neglected while we talk about mass-mass attraction.
Electromagnetic Force is the second strongest force we have in our universe. But, its somehow different. Other forces we have are only attractive forces whereas, this is both attractive and repulsive in nature. Its also responsible for the mass mass attraction because if we have two differently charged object,they will be attracted to each other.
Gravitational Force is the weakest of all forces but, its range is the biggest. And, its the major force that can be considered responsible for this attraction. According to Einstein believe of Gravitational Force it actually very indifferent to other forces. Because, other forces are produced due to some elementary particles or bosons like gluons, and protons but, Gravity is totally different. It also has a messenger particle according to quantum mechanics “The Graviton” but, Relativity says that its not actually a force but, a outcome by the structure of space. Its due to the curvature produced by mass on the Fabric of Space - Time which looks like
And this curvature formed by earth in space time the space tends to get stable and be back in it mean position that is some Restoring Force acts on it due to which we say that gravity is not a force of pull but, a push.
Space push every object towards every other up to its ablility and capability to do the same.

Strong Nuclear Force
Electromagnetic Force
Weak Nuclear Force
Gravitational Force
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