Problem understanding Newtons third law ...

In summary, on a frictionless surface with three blocks, a 42N force acts on the 3kg block and the force exerted by the 1kg block on the 2kg block is 14N. The force exerted by the 2kg block on the 1kg block is also 14N due to the string connecting the blocks. Both blocks should stay in place.
  • #1
Warlic
32
0

Homework Statement



upload_2015-11-5_19-55-25.png
[/B]
Three blocks move on a frictionless surface and a 42N force acts on the 3kg block.
The force exerted by the 1 kg block on the 2 kg block is 14N.

What is then the force exerted by the 2 kg block on the 1kg block? If it is 14N, then shouldn't the 2kg block stay in place and not move? Shouldn't then the 1kg block also stay in place?

2. Homework Equations

F=ma?

The Attempt at a Solution

 
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  • #2
upload_2015-11-5_20-2-15.png

This would be the correct figure; 3kg block pulled by a force of 42N, and the 1 kg and 3kg block are connected by a string.
 
  • #3
Warlic said:
If it is 14N, then shouldn't the 2kg block stay in place and not move? Shouldn't then the 1kg block also stay in place?

Don't forget the force applied due to the string connecting the blocks; the 14N-force isn't the only one affecting the block 1/2 - system.
 

What is Newton's third law?

Newton's third law states that for every action, there is an equal and opposite reaction. This means that when a force is applied to an object, the object will push back with the same amount of force in the opposite direction.

Why is Newton's third law important?

Newton's third law is important because it explains how objects interact with each other and how forces cause motion. It also helps us understand how to calculate forces and predict the motion of objects.

Can you give an example of Newton's third law in action?

One example of Newton's third law is when you push a balloon filled with air, the air inside the balloon pushes back with the same force, causing the balloon to move in the opposite direction.

Does Newton's third law apply to all objects?

Yes, Newton's third law applies to all objects, regardless of their size, shape, or mass. It is a fundamental concept in physics that applies to all interactions between objects.

How is Newton's third law related to the other laws of motion?

Newton's third law is closely related to the other laws of motion, specifically the first and second laws. The first law (inertia) explains how objects at rest stay at rest or in motion unless acted upon by a force. The second law (acceleration) explains how the net force on an object causes it to accelerate. Newton's third law helps us understand the forces that cause this acceleration.

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