Final answer:
Newton's 3rd law of motion, often summarized as 'For every action, there is an equal and opposite reaction,' means that forces always occur in pairs with equal magnitudes, but in opposite directions, and these forces do not cancel out as they act on different bodies or systems.
Step-by-step explanation:
Newton's 3rd law of motion states: For every action, there is an equal and opposite reaction. This means that any force exerted onto a body will generate a response from that body in the form of a force of equal magnitude but in the opposite direction. The law emphasizes that forces always occur in pairs, often referred to as action-reaction pairs.
An example of this can be seen when you push against a wall, the wall pushes back with an equal force. Similarly, when an object is at rest on a surface, the surface applies a force that directly opposes the weight of the object, which is why the object does not fall through the surface.
Important to remember that the action and reaction forces don't cancel out as they act on different bodies or systems. This law represents a basic symmetry in nature and is concisely summed up as: for every force, there is an equal and opposite force.
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