## Before the acceleration. ? 3. Newton’s third

Before investigating the three different car safety features, one must understand Newton’s laws of motion:

1. Newton’s first law of motion states, “A body at rest will remain at rest, and a body in motion will remain in motion unless it is acted upon by an external force.” This means that something cannot move, stop or change direction by itself unless a force is acting on it.

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2. Newton’s second law of motion states that when a massive body is acted upon by an external force, the force acting on the object is equal to the mass of that object multiplied by its acceleration.

The law is written in the mathematical form as f = ma where f is the force, m is the mass and a is the acceleration.

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3. Newton’s third and final law states, “For every action, there is an equal and opposite reaction.” The law describes what happens when a body applies force onto another body. When one body pushes against another, the second body pushes back with force as well.