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Newton's Laws

Question

What is the 3rd of Newton's laws?

2 years ago

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127 Replies

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R

Reginald Wisoky


127 Answers

K
Kanika

The 3rd law of Newton's states that when two bodies interact, they apply forces to one another that are equal in magnitude and opposite in direction. The 3rd law is also known as the law of action and reaction.

C
Chenai Gwenzi

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

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When two objects interact, the forces they exert on each other are equal and opposite.

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Newton's Third Law of Motion states:

"For every action, there is an equal and opposite reaction."

This law means that if object A exerts a force on object B, then object B simultaneously exerts a force of equal magnitude in the opposite direction back on object A. The forces always occur in pairs, and they act on different objects. This law is fundamental to understanding the interactions between objects and plays a crucial role in explaining how objects move and interact in the universe.

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Falak Hussain

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!

A
Akanksha Saroch

For every action there is equal and opposite reaction

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Hi Reginald,


Newton's 3rd Law of Motion states that for every force there is an equal and opposite and force in nature.


This means that if there are to objects, object A and object B, and object A exerts a force of 60N on the right onto object B, then object B must exert an equal force of 60N in the opposite direction.

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A
Andrew Mainey

If body A exerts a force on body B.

Body B will exert an equal and opposite force (of the same type) on Body A

G
Graham Martin

Whenever two objects interact, they exert equal and opposite forces on each other.

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Newton's third law states that when two bodies interact, they apply forces to one another that are equal in magnitude and opposite in direction. The third law is also known as the law of action and reaction.

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Every action has an equal and opposite reaction. Therefore when two objects interact they will exert on each other forces that are equal in magnitude but opposite in direction.

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S
Sandeep Saji

Every action has an equal and opposite reaction.

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Avoid thinking about action and reaction or you will be confused by the book and the table example above. The proper statement is "Object A forces object B means object B forces object A with an equal and opposite force." The two forces in a Newton's Third Law pair are 1. equal magnitude 2. opposite direction 3. Act on different objects 4. Are THE SAME TYPE OF FORCE.

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L
Latoya

Newton's 3rd law is as follows: All forces come in pairs. These forces are:

  1. the same type of force (e.g. both are gravitational)
  2. have the same size (magnitude)
  3. act in opposite directions to one another
  4. act at the same time,
  5. act on different objects


The 'action = reaction' referred to is this pair of forces that must fit all of these 5 points to be considered an action-reaction pair.


A common mistake is thinking that a book lying on a table has weight and normal reaction as its action-reaction pairs. This is incorrect because a) both forces act on the same object (the book) and b) these are not the same type of force - normal reaction is electromagnetic whereas the weight of the book is gravitational. The fact that both of these forces have the same magnitude and act in opposite directions is an example of equilibrium instead.


But all forces come in pairs so what are the other 2 forces that do make up the action-reaction pairs? Well the first is the gravitational pull from the Earth, this forms the action-reaction pair with the weight of the book. Secondly, the normal reaction of the book onto the table with the normal reaction of the table onto the book forms the other action-reaction pair.


H
Hamdaan Sheikh

Formally known as; When Body A exerts a force upon Body B, Body B will exert an equal and opposite force upon Body A


A more commonly known phrase is; "every action has an equal and opposite reaction"

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