law of action and reaction
Quick Summary
The law of action and reaction, also known as Newton's third law of motion, states that for every action, there is an equal and opposite reaction. This means that when two bodies interact, they exert forces on each other that are equal in magnitude and opposite in direction. These forces always act on different bodies and never on the same body.123
For example, a rocket expels exhaust gases downward (action), and the gases push the rocket upward (reaction). Similarly, when you push on a wall, the wall pushes back on you with an equal force. This principle is fundamental to understanding mechanics and how forces interact in the physical world.21
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- momentum
According to Newton’s third law, the particles exert equal and opposite forces on one another, so any change in the momentum of one particle is exactly balanced by an equal and opposite change of the momentum of another particle. Thus, in the absence of a net external…
Read MoreAccording to Newton’s third law, the particles exert equal and opposite forces on one another, so any change in the momentum of one particle is exactly balanced by an equal and opposite change of the momentum of another particle. Thus, in the absence of a net external…
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mechanicsConservation of momentumAccording to Newton’s third law, the particle must apply an equal and opposite force −F a to the external agent. The momentum p a of the external agent therefore changes according to
Read MoreAccording to Newton’s third law, the particle must apply an equal and opposite force −F a to the external agent. The momentum p a of the external agent therefore changes according to
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