# Describe Newton's laws.

### 2 Answers | Add Yours

Newton's First Law- An object in motion tends to stay in motion unless an external force is applied to it. For example, if you hit a baseball, it would keep on traveling except for the the fact that friction slows it down and gravity pulls it to Earth. This is also called Inertia.

Newton's Second Law-Is Force =Mass X Acceleration

If you want to calculate the force of a moving object, if you know its mass and how quickly it is moving over a period of time, you can calculate its force. The direction of the force vector is the same as the direction of the acceleration vector. Acceleration is directly proportional to the force but inversely proportional to the mass of an object.

Newton's Third Law- For every action, there is an equal but opposite reaction. When a rocket is launched as the rocket fuel ignites and the exhaust is released out of the back of the rocket, the rocket is propelled forwards.

**Sources:**

First law: The velocity of a body remains constant unless the body is acted upon by an external force. Second law: The acceleration a of a body isparallel and directly proportional to the net force Fand inversely proportional to the mass m, i.e.,F = ma. Third law: The mutual forces of action and reaction between two bodies are equal, opposite and collinear.