# Newton three laws of motion

**Learn** about Newton three laws of moting. Newton three laws of moting explains planatory motions very well with assumption that gravity act on its object instantaneously which Einstein proved wrong in general relativity. Here is the Newton three laws of motion:

- First law is law of inertia. In the absence of a net force, a body either is at rest or moves in a straight line with constant speed.
- A body experiencing a force F experiences an acceleration a related to F by
- F = m x a, where m is the mass of the body. Alternatively, force is equal to the time derivative of momentum.
- The third law is law of action and reaction. Whenever a first body exerts a force F on a second body, the second body exerts a force −F on the first body. F and −F are equal and opposite in direction.

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