How can physicists use Newton’s laws of motion and universal gravitation to predict objects’ motion?

Newtons law of universal gravitation is the phenomena in which Newton said that every particle in environment will attract other particles in the space.  

Explanation:

Newton law of motion and gravitation attract forcefully which is direct proportional to the masses of the particles and inversely proportional to the square of the distances between the centers. Other physicist used Newtons law in research related to motion or to find out the distance between earth and sun. Because this law is about the mass of the objects. When the mas of an object is doubled, the force between the objects get too doubled. When the mass of the two objects is doubled the gravitational pull between these two objects gets doubled. Sir Isaac Newton first gave this law when see fall down an apple from tree.

Formula is : F = G  Mm/r2 Here G is gravitational pull that is constant.

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2

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