Here is your short paragraph on Gravity!
Gravity is the earth’s attractive force. The force of gravity attracts physical objects towards the earth’s center.
Because of the force of gravity we fall down when we jump from building. The force of gravity or gravitational force is greater near the earth’s surface & becomes less while going up or away from the surface of the earth.
At a certain point above the earth’s surface this force becomes 0. All planets moving in the Milky Way have their own gravity. The intensity of force varies planet to planet. For instance, Moon’s gravitational force is 1/6th as compared to earth’s gravitational force. When we throw an object up it is due to the force of gravity it falls down. This force of gravity is dependent upon 3 factors such as-
- The mass/ weight of the massive object
- The mass/ weight of the smaller body &
- The separation among the two (this distance is measured in terms of their geometrical centers).
In physics the force of gravity is explained by Newton in his ‘Law of Universal Gravitation’. Newton in his law does not stipulate a smaller boy & a massive body.
Instead he believed that the law of gravity affects 2 bodies irrespective of their weights. No matter either one is heavier than the other. He believed that the force of gravity is constant having the value equals to 6.673×10-11 N m2 kg-2. However an individual cannot measure the force of gravity. The heavier the object is the more the force of gravity is over it.
In physics the mathematical relationship that explains acceleration caused due to force of gravity is-
F = (G x m1 x m2) / r2
- “F” means “force of gravity”
- “G” means “gravitational constant”
- “m1” means “mass of the 1st object” (let’s say it has move weight comparatively)
- “m2” means “mass of the 2nd object” (let’s say it has less weight comparatively)
- “r” means “the separation among the 2 masses”
Things to note:-
I. The force of gravity is directly proportional to “m1”. Hence all other things being equal, a planet having more weight would exert large force as compared to the object. So the object will be heavier on Jupiter as compared to earth.
II. The force of gravity is directly proportional to “m2”. Hence more the weight of the object more is the force of gravity.
III. Gravity is universally proportional to square of “r”. Hence the object would be heavier in earth’s surface as compared to far away than the earth’s surface.
IV. “F” is universally proportional to square of “r”. It would vary with the change in “r”. Hence if we move away from the earth’s surface “f” would decrease & become negligible at some point.