# acceleration of gravity

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## acceleration of gravity

Symbol:*g*. The acceleration to the center of a planet (or other massive body such as a natural satellite) of an object falling freely without air resistance, i.e. acceleration due to downward motion in a gravitational field. It is equal to

*GM*/

*R*

^{2}, where

*G*is the gravitational constant and

*M*and

*R*are the mass and radius of the planet. The acceleration is thus independent of the mass of the accelerated object, i.e. it is the same for all bodies (neglecting air resistance) falling at the same point on the surface of the planet, satellite, etc.

On Earth the value of the acceleration of gravity is about 9.81 meters per second per second. The value varies from place to place on the Earth's surface because of different distances to the Earth's center and greater acceleration toward the equator. In addition, it is affected by local deposits of light or heavy materials. See also microgravity; weight; weightlessness.

## Acceleration of Gravity

(or acceleration of free fall), the acceleration imparted to a free material particle by the force of gravity. Such acceleration would be undergone by the center of gravity of any body if the body were to fall to earth in a vacuum from a small altitude. Like the force of gravity, the acceleration of gravity depends on the latitude φ and the elevation *H* above sea level. The acceleration of gravity *g* is approximately 978.049(1 + 0.005288 sin^{2} φ – 0.000006 sin^{2} 2φ) – 0.0003086*H*. At the latitude of Moscow at sea level *g* = 981.56 cm/sec^{2}.

## acceleration of gravity

[ak‚sel·ə′rā·shən əv ′grav·ə·dē]^{2}but varies with latitude and elevation. Also known as acceleration of free fall; apparent gravity.

## acceleration of gravity (g)

*g*is 386.089 inches per second square = 32.1740 feet per second square = 9.80665 meters per second square.)