How Gravity Works

Gravity is the cause of things with mass or energy being drawn to each other. That is why apples drop toward the ground and planets orbit around stars. Indeed, gravity is essential in our daily life.

Gravity is a natural occurrence through which all things with mass or energy, comprising planets, stars, galaxies and also light, are drawn to (or descend toward) one another. On Earth, gravity provides weight to physical objects and the Moon’s gravity induces the oceans’ tides. The gravitational attraction of the original gaseous matter  in the Universe induced it to start combining and creating stars. It caused the stars to assemble into galaxies, so gravity is accountable for many of the large-scale compositions in the UniverseUniverse. 

Newton’s Gravity

In the 1600s, an English mathematician and physicist named Isaac Newton were seated under an apple tree, the fable tells us. An apple dropped on his head and he began speculating why the apple was drawn to the land in the first place.

Newton broadcasted his Theory of Universal Gravitation in the 1680s. It fundamentally expressed the idea that gravity was a conventional force that works on all matter in the Universe and is a role of both mass and distance. The theory affirms that each particle of matter draws every other particle (for example, the units of “Earth” and the particles of “you”) with an energy that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.

So the distance apart the particles are the less substantial the particles, the fewer the gravitational force.

The typical formula for the law of gravitation is :

Gravitational force = (G * m1 * m2) / (d2)

Gravitational force = (G * m1 * m2) / (d2)

Where G represents the gravitational constant, m1 and m2 represent the masses of the two objects for which the force is being calculated and d denotes the distance amid the centres of gravity of the two masses.

G comprises the value of 6.67 x 10-8 dyne *cm2gm-2. So if you place two 1-gram objects 1 centimetre distant from one another, they will draw each other with the force of 6.67 x 10E-8 dyne. A dyne is equivalent to about 0.001 gram weight, denoting that if you have a dyne of force accessible, it can raise 0.001 grams in Earth’s gravitational field. 

Therefore, 6.67 x 10E-8 dyne implies a minuscule force.

When we talk about enormous bodies like the Earth, nevertheless, which comprise a mass of 6E+24 kilograms, it adds up to a quite dominant gravitational force. That’s why we are not floating around in space at present.

The force of gravity employed on an object is moreover that object’s weight. When we weigh ourselves on a scale, the scale comprehends how much gravity is working on our bodies. The formula to establish weight is:

Weight = m * g

Where m denotes an object’s mass and g denotes the acceleration because of gravity. Acceleration because of gravity on Earth is 9.8 m/s² — it never alters, despite an object’s mass. Therefore if we were to plunge a stone, a pen and a couch from a roof, they’d strike the ground simultaneously.

For centuries, Newton’s theory of gravity pretty much dwelled alone in the scientific society. That was modified in the early 1900s.

Einstein’s Gravity

In the early 1900s, Albert Einstein proposed an alternative explanation of gravity. In 1921, he was awarded the Nobel Prize in Physics. A part of Einstein’s renowned General Theory of Relativity, this theory offered a new interpretation of Newton’s Law of Universal Gravitation. When it comes to gravity, Einstein didn’t think of it as an actual force, but rather as a distortion in the geometry of space-time. 

If no external forces are at play, an item will always travel in the straightest possible line. This is a fundamental tenet of physics. Without an external force, two objects on parallel trajectories will always remain parallel. They’re never going to get together, no matter how hard they try.

But the fact is they do gather. Particles that begin off on parallel paths at times end up crashing. Newton’s theory affirms that this can transpire because of gravity, a force drawing those objects to one another or a single, third object. Einstein also says this happens because of gravity — except in his theory, gravity isn’t a force. He calls it a curve in space-time.

This is still the straightest possible path for Einstein’s objects, but the straightest possible journey is now along a spherical road due to space-time distortion. So, two things that were travelling on a flat plane are now travelling on a spherical plane. Moreover, two straight lines on the sphere end in the same place.

A newer approach to understanding the gravitational pull uses particle and wave models to explain the phenomenon. Gravitons, according to one theory, are responsible for the attraction between objects. Gravitons, on the other hand, have never been observed. No gravitational waves have been observed, which are supposed to be created when an object is accelerated by an external force, either.

Conclusion

Gravitons or no gravitons, we understand that what goes up should come down. This is the importance of gravity in our daily life. Maybe someday, we’ll know exactly why. But till then, we can be satisfied just distinguishing that planet Earth won’t go dashing into the sun anytime soon. Gravity is keeping it securely in orbit.