Search results
Results from the WOW.Com Content Network
The portion of the mass that is located at radii r < r 0 causes the same force at the radius r 0 as if all of the mass enclosed within a sphere of radius r 0 was concentrated at the center of the mass distribution (as noted above). The portion of the mass that is located at radii r > r 0 exerts no net gravitational force at the radius r 0 from
A gravitational field is used to explain gravitational phenomena, such as the gravitational force field exerted on another massive body. It has dimension of acceleration (L/T 2) and it is measured in units of newtons per kilogram (N/kg) or, equivalently, in meters per second squared (m/s 2). In its original concept, gravity was a force between ...
In physics, gravity (from Latin gravitas 'weight' [1]) is a fundamental interaction primarily observed as mutual attraction between all things that have mass.Gravity is, by far, the weakest of the four fundamental interactions, approximately 10 38 times weaker than the strong interaction, 10 36 times weaker than the electromagnetic force and 10 29 times weaker than the weak interaction.
Newton's laws are often stated in terms of point or particle masses, that is, bodies whose volume is negligible. This is a reasonable approximation for real bodies when the motion of internal parts can be neglected, and when the separation between bodies is much larger than the size of each.
According to general relativity, mass distorts spacetime and gravity is a natural consequence of Newton's First Law. Mass tells spacetime how to bend, and spacetime tells mass how to move. In general relativity gravitational energy is extremely complex, and there is no single agreed upon definition of the concept.
In other words, passive gravitational mass must be proportional to inertial mass for objects, independent of their material composition if the weak equivalence principle is obeyed. The dimensionless Eötvös -parameter or Eötvös ratio η ( A , B ) {\displaystyle \eta (A,B)} is the difference of the ratios of gravitational and inertial masses ...
The standard gravitational parameter GM appears as above in Newton's law of universal gravitation, as well as in formulas for the deflection of light caused by gravitational lensing, in Kepler's laws of planetary motion, and in the formula for escape velocity. This quantity gives a convenient simplification of various gravity-related formulas.
In Newtonian gravity, the source is mass. In special relativity, mass turns out to be part of a more general quantity called the energy–momentum tensor, which includes both energy and momentum densities as well as stress: pressure and shear. [40] Using the equivalence principle, this tensor is readily generalized to curved spacetime.