Editing Acceleration (section)

===Other forms===
An object moving in a circular motion—such as a satellite orbiting the Earth—is accelerating due to the change of direction of motion, although its speed may be constant. In this case it is said to be undergoing ''centripetal'' (directed towards the center) acceleration.

[[Proper acceleration]], the acceleration of a body relative to a free-fall condition, is measured by an instrument called an [[accelerometer]].

In [[classical mechanics]], for a body with constant mass, the (vector) acceleration of the body's center of mass is proportional to the net [[force]] vector (i.e. sum of all forces) acting on it ([[Newton's laws of motion#Newton's second law|Newton's second law]]):
<math display="block" qid=Q2397319>\mathbf{F} = m\mathbf{a} \quad \implies \quad \mathbf{a} = \frac{\mathbf{F}}{m},</math>
where {{math|'''F'''}} is the net force acting on the body, {{mvar|m}} is  the [[mass]] of the body, and {{math|'''a'''}} is the center-of-mass acceleration. As speeds approach the [[speed of light]], [[Special relativity|relativistic effects]] become increasingly large.