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Newton's third law of motion states that for every action, there is an equal and opposite reaction.
This means that whenever an object exerts a force on another object, the second object exerts an equal and opposite force back on the first object. These forces are known as action and reaction forces.
For example, if you push a book across a table, the book exerts an equal and opposite force back on your hand. This is why you can feel the resistance of the book as you push it.
Mathematically, we can express this law as F₁ = -F₂, where F₁ is the force exerted by object 1 on object 2, and F₂ is the force exerted by object 2 on object 1. The negative sign indicates that the forces are equal in magnitude but opposite in direction.
It's important to note that these forces always act on different objects, and they never cancel each other out. This is because they are acting in opposite directions and on different objects.
Understanding Newton's third law of motion is crucial for understanding how objects interact with each other in the physical world. It helps us to analyse and predict the motion of objects, and it forms the basis for many important scientific and engineering principles.
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