Definition:Gravity

Definition

Gravity is the tendency of bodies with mass to attract each other.

When used in an unqualified sense, it is usual for the term force of gravity to mean the downward force on a body at the surface of Earth.

From Gravity at Earth's Surface, this is approximately $9.8 \ \mathrm N \ \mathrm{kg}^{-1}$

The force of gravity varies across the Earth's surface, and therefore it makes little sense to use it as a standard.

However, the CGPM adopted a standard value of Acceleration Due to Gravity at Earth's Surface of $9.806 \, 65 \ \mathrm N \ \mathrm{kg}^{-1}$ in $1901$.

The gravitational force on a body $B$ is the force which is exerted on $B$ as a result of the gravitational field whose influence it is under.

Gravity is also known as gravitation.

In common usage it is often referred to as the force of gravity, in particular at the surface of Earth.

The word gravity derives from a Latin word meaning weighty.