What Does Force of gravity Mean
We explain what the force of gravity is, how and by whom it was discovered. Also, some examples of this force.
What is the force of gravity?
The force of gravity (or simply "gravity") is one of the fundamental interactions of nature , which causes bodies endowed with mass to attract each other with greater intensity to the extent that they are more voluminous or are closer to each other . The principle that governs this interaction is known as "gravitation" or "gravitational interaction", and responds in physics to what is described by the Law of Universal Gravitation .
It is the same attraction that the Earth exerts on bodies and objects that are close to it, including us, and that causes things to fall. It also determines the movements of the space stars (planets orbiting the Sun or moons and artificial satellites orbiting these planets in turn .
Unlike the other fundamental interactions in the Universe (which are strong and weak nuclear forces, and electromagnetism ), the force of gravity inexplicably predominates over enormous distances , while the others occur over much shorter distances.
The gravity is studied in different theoretical frameworks depending on whether it is a (classic) or relativistic mechanical approach.
Usually the units used to work with gravity are units of weight such as kilograms of force, or Newtons (N). This is because the weight of a body is equal to its mass times the acceleration of gravity that the gravitational force of the Earth exerts on it. That is, do not confuse gravity with gravitational force. Gravity is an acceleration and not a force like weight.
The acceleration of gravity on the earth's surface reaches about 9.80665 m / s2.
It can help you: Gravitational field
Who discovered the force of gravity?
The force of gravity was not properly "discovered", since its effects have been known from the beginning of humanity and thought . However, the universal law of gravitation that explains it and allows it to be calculated was proposed by Isaac Newton in 1687, supposedly after being hit by an apple on the head, while resting in the English countryside.
This episode would have revealed to the English scientist that the same force that makes things fall to the ground , keeps the planets in their orbit with respect to the Sun and their satellites with respect to them. This was a turning point in the history of modern physics.
Subsequently, the physicist Albert Einstein in the twentieth century, based on Newton and his own findings, postulated his Theory of General Relativity , in which he reformulated some aspects of Newtonian gravitation.
Thus was inaugurated a new perspective on gravity, called "relativistic." According to her, gravity is not a universal measure of force, but a variable one , and not only affects space but also time .
Examples of the force of gravity
The force of gravity can be studied in the following examples:
- The free fall of a body on the earth's surface . The mass of the planet attracts us to it and acts on our mass by printing an acceleration. For this reason, an object that falls for one minute hits harder than one that falls for one second.
- An object thrown into the sky. A cannonball, for example, will fly in a straight line until it suffers a loss of acceleration, the result of gravity, curving its trajectory. When this exceeds the initial force of the explosion, the object will fall and stop moving.
- The orbiting of the moon around our planet. This movement is due to the fact that the moon is trapped in the Earth's gravitational field, at such a distance that it cannot move away in a straight line, nor can it fall towards us and fall.
- Falling meteorites. Attracted by their enormous force of gravity, many meteorites enter the atmosphere of Jupiter, Saturn and other very massive planets, torn from their natural orbit around the Sun.