Gravitation

Unlike magnetic force, gravitational forces are always attractive and exist between all objects, object to all matter without exception, even light. The force of gravity affects objects and materials constantly. For example, if a parachutist board a plane that takes it up and jumps out of it, the effect of gravity is particularly visible when jumping off a plain, but it works at any moment. Gravitational forces do not depend on the characteristics of the environment, similarly to the magnetic effect, nor can they „diminish“ or „obscure“ their effects by obstacles. For example, gravitational forces cause Earth‘s attractiveness and other cosmic bodies, keeping planets in orbits around the Sun; Moon and satellite in orbit around Earth.

Newton and gravitation

The first to investigate gravitational forces was Isaac Newton. The force causing body to fall vertically to Earth is identical to the force that causes the planets to orbit around the Sun, and the Moon around the Earth. Based on this idea and other calculations in which Newton used the well-known Kepler equation, the wording of the so-called The Newton´s gravitational law, according to which two bodies are mutually attracted by force (gravitational), which is the greater, the greater the component weight of both bodies (directly proportional to the weight of both bodies) and the greater, the smaller the distance between them (Indirectly proportional to the mutual distance of two bodies).

For example, the Earth and the Moon act more intensely than the Earth, and eg. Jupiter because Earth and the Moon are closer together. In addition, the Earth is more attractive because it is heavier than the Moon, for example, by comparing the effects of gravity on Earth and the Moon, on the Moon, astronauts are attracted to the surface by much less attractive power compared to Earth.

Free fall

The free fall is a movement in which the body is released from a certain height above the earth‘s surface. The free fall rate of the body does not depend on its weight. This means that bodies of different masses running from the same height should fall to the ground at the same time as the acceleration of these bodies by the force of gravity is not dependent on the mass of the bodies. However, the atmosphere has a significant effect on falling objects, so it is only possible to observe the same acceleration when two bodies of different masses are dropped in a vacuum environment.

The idea that heavier bodies fall to the ground is more of a relatively old Aristotelian perception of gravitational forces. This perception has been overcome by the experiments conducted by Galileo Galilei. Examining the motion of their bodies triggered from Pisa‘s oblique tower proved that the speed of bodies falling freely does not depend on their weight. His research question was: If a person from the tower drops 10 and a 5-pound ball at the same time, which first falls to the ground? Will gravity act more on a 10-pound ball? Even after repeated observations, both balls hit the ground almost at the same time.

It is important to note that the size and shape of objects can also affect the rate of fall if the observation is carried out under natural conditions in the presence of the atmosphere (air). Air resistance significantly slows the fall of objects. For example, if we take two equally sized pieces of paper and one of them shrinks into a ball and drop it out of the same height at once, the paper ball will definitely fall. However, not because the Earth‘s gravity has a different force on these two objects, but for the air resistance that is ubiquitous. If there was no air around us, all objects would fall at the same speed. However, the air is hampered by the fall of objects, and the more the surface of the object is. The parachute works on this principle. Although the gravitational force attracts the parachute to the ground, the air accumulates beneath the dome of the parachute, slowing it down and slowing down its fall.

In many cases, observing the fall of objects in natural conditions, it is even necessary to take into account the wind, for example in the case of the procedure used by Galileo Galilei to disprove Aristotle‘s thesis on the different effects of the Earth‘s attractive force on various heavy objects.

Weight mass and gravity

When accurately grasping the effects of gravity on objects and materials, it is important to realize the difference between weight, mass and gravity.While mass represents the amount of substance that the materials and objects are made up of, the weight is essentially the result of an attractive gravitational force on the mass and is expressed in grams. Gravity is the pressure force by which the body located in the gravitational field acts on the pad and is expressed in Newtons units. The body is gravitated if it is in a state of equilibrium between two forces, the gravity pushing down and the opposite force acting from the Earth, pushing upwards (e.g., the centrifugal force caused by the rotation of the Earth around its axis).

Effect of gravitational force Months at high tide and low tide

If we observe astronauts float in their spacecraft while orbiting Earth, we have no doubt that they are in a weightless state (or the gravity is minimal, never completely zero). But they are not in a state of no force because the spacecraft is moving in the Earth‘s gravitational field. For the usual orbits, the intensity of the gravitational field is almost the same as on the Earth‘s surface, but the effect of the Earth‘s centrifugal force caused by its rotation is diminishing

The effect of the Moon‘s gravitational force on Earth is the easiest to observe on the tide. The tides are increasing and decreasing the water levels of the seas and oceans that we observe on their shores. Finally, it is important to note that there is no established scientific theory about what causes gravitational force to exist.