- What is a gravitational field?
- Gravitational field intensity
- Gravitational potential
- Examples of gravitational field
We explain what gravitational fields are and how their intensity is measured. Also, examples of gravitational field.
What is a gravitational field?
The gravitational field or gravitational field is called the set of forces that represents, in physical, what we commonly call the force of gravity: one of the four fundamental forces of theuniverse. The gravitational force is an attractive force between massive objects.
According tologic From gravitational fields, the presence of a body of mass M generates in the space around it a field of gravitational forces that can alter the trajectory of massive objects under its influence.
In fact, if another body of mass M approaches the gravitational field of M, we will notice that its movement is altered by the force of gravity. And, according to the theory of relativity, even the weather It would itself be affected by these forces, distorting it and giving rise to singularities such as black holes, astronomical objects whose gravitational fields are so strong that not even the light manages to escape from them.
Gravitational fields were for many years eminently theoretical in nature, understood by classical (Newtonian) physics as a vector field, and by relativistic physics as a second-order tensor field, but the discovery in 2016 of the waves Gravitational pulls by the scientists in the LIGO experiment seem to shed new light on this matter.
Gravitational field intensity
The intensity of the gravitational fields or, what is the same, the acceleration of the gravity (or simply gravity) is represented in classical physics by the symbol g and as a field of vectors, that is, of lines endowed with meaning and address.
It is commonly defined as the force per unit of mass you will experience a particle determined in the presence of a mass distribution. It is usually expressed in Newtons per kilogram (N / kg).
The formula for its calculation, then, would be:
g = lim m → 0 F / m, where m would be a test mass and F the gravitational force acting on it.
Gravitational potential
The gravitational potential of a gravitational field is, in Newtonian mechanics, a scalar quantity that is measured in joules per kilogram (J / kg) and is defined as the amount ofjob per unit of mass necessary to transport a body at a constant speed from infinity to a certain point in the gravitational field in question.
The gravitational potential is calculated based on the following formula:
V = - GM / r, where V is the gravitational potential, G is the universal gravitational constant and r is the distance from the point where we want to calculate the potential to the position of the mass M.
Examples of gravitational field
A perfect example of a gravitational field is that of the Solar system, in which the planets orbit around the Sun, attracted by the gravitational forces of their mass.
Another example is the Earth's gravitational field, the one generated by the planet Earth around it and that we can appreciate every time we drop an object into it. I usually. The mass of the Earth is approximately 5974 x 1024 kg, which generates a remarkable gravitational field around it.
It is known that the Earth's gravity is more or less than 9.8 N / kg, that is, an acceleration of 9.8m / s in the direction of the center of the Earth. This value may vary slightly depending on geographic location, but assuming it to be constant across the entire surface of the Earth is a very good approximation.
In addition, the gravitational field will be more intense in the vicinity of the Earth's surface, than in the outer layers of the Earth. atmosphere.