What is the 3rd of Newton's laws?

Every action has an equal and opposite reaction

The third law states that, a mass1 experiencing a contact force from a mass2, will generate a force of the same magnitude but with opposite direction of the original. In other words, if mass1 exerts a contact force on mass2, then mass2 will exert the same force on mass1.

If body A applies a force on body B, then body B will apply an equal and opposite force on body A

Newton’s third law is about action and reaction forces. For every Action force there is a equal and opposite reaction force. These forces act on different bodies and causes acceleration in the bodies depending on their mass.

For every action is an equal and opposite reaction

Whenever two objects interact, the forces they exert on each other are equal and opposite. So for every action there is an equal and opposite reaction!

Every action has an equal and opposite reaction. So to speak, when you're standing on the ground, your weight pulls you downwards. At the same time, a force called the normal reaction force is pushing your weight upwards. The normal reaction force makes it so that you don't go through the ground. Weight is balanced with the normal reaction force. Hope that helps!

The well known phrase "for every action, there's an equal and opposite reaction" sums up the 3rd law of motion.

The best example is the recoil of a gun - if you think of the gun pushing the bullet forwards, the bullet must push the gun backwards with an equal force.

Newton's 3rd Law is: for every action, there is an equal but opposite reaction. For example, if you were to push a door with a force of 10N, the door is also pushing against your hand with a force of 10N.

For every action, there is an equal and opposite reaction. Think about momentum, how do we calculate it, what happens for example to a football when we kick it.

Newton’s third law states that for every action there is an equal and opposite reaction. When 2 objects interact they exert equal and opposite forces on each other

Newton's 3rd law states that...

if an object A exerts a force on object B,

then object B will exert a force

of equal magnitude but opposite direction onto A.

This law is often remembered as the "for every action there is an equal and opposite reaction", but do not write this in the exam!

The forces involved are often referred to as "interaction pairs".

Example 1: an athlete stretches by pushing on a wall; the wall pushes the athlete back.

Example 2: the gravitational force of Earth pulls a person; so the person also pulls on the Earth.

It is very important to notice that the two forces act on different objects, so they never cancel out.

In the second example, the person's force is just as large as the Earth's (even if it feels weird!). However, the effect of the force is very different because the mass of the person is much much smaller than that of Earth.

Here is a typical misconception about forces on a sitting person.

"Because of Newton's 3rd law, the chair pushes back. So, the two forces are balanced." --- the reasoning here is incorrect.

It is true that there is a force from the chair on the person (this is called the "normal reaction force") and it is true that there is a force from the person onto the chair.

BUT -- the weight acts on the person, and the push from the chair acts on the person; these are the balanced forces.

The pushing force that the person exerts on the chair is irrelevant! When thinking about balanced forces, we are focusing on ONE object only.

Every action has an equal and opposite reaction!

Hi Reginald, Newton's 3rd law of motion states that any action has an equal opposing force that the object carrying out the action will experience. For instance, if you stand near a wall and push the wall with some force, you will experience the same force you applied on the wall on yourself, which will push you away from the wall.

Newton's 3rd law states that; for every action, there is an equal and opposite reaction. i.e. If you apply a force to an object, the object will apply the same for to you, but in the opposite direction.