Some calculations in Newton's Third Law

In summary, we discussed the relationship between force, mass, and acceleration according to Newton's third law. We also touched on the concept of rebound height and how it relates to an object's elasticity. Overall, it is important to consider the signs of accelerations and the effects of outside factors, such as air resistance, on objects in motion.
  • #1
ahmed emad
43
2
Hello,
1- IF we have an object has 200 kg and we also have a machine has 5 kg and pushes that object with force of 600 n , in Newton third law it must be another force =-600n then : the acceleration of the object must be 3 m\s^2 and the acceleration of the machine is 120 m\s^2 , Am I wrong??

2- if I am in vacuum and I dropped an apple and the distance between my hand and the floor =5 m , is the apple must lunge with 5 m also?? (I said vacuum because I think that the thing causes apple not lunge at the same distance is the air resistance )

And thank you.
 
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  • #2
ahmed emad said:
Hello,
1- IF we have an object has 200 kg and we also have a machine has 5 kg and pushes that object with force of 600 n , in Newton third law it must be another force =-600n then : the acceleration of the object must be 3 m\s^2 and the acceleration of the machine is 120 m\s^2 , Am I wrong??
You are essentially correct, but be careful about the signs of the accelerations. They would be in opposite directions, so they would have opposite signs in any coordinate system.
2- if I am in vacuum and I dropped an apple and the distance between my hand and the floor =5 m , is the apple must lunge with 5 m also?? (I said vacuum because I think that the thing causes apple not lunge at the same distance is the air resistance )
I don't understand your use of the word "lunge" here.
 
  • #3
FactChecker said:
You are essentially correct, but be careful about the signs of the accelerations. They would be in opposite directions, so they would have opposite signs in any coordinate system.I don't understand your use of the word "lunge" here.
sorry I am not talk English extremely ,I am from egypt
I meant Rebound
and thank you
 
  • #4
Ok. The rebound height would depend on the elasticity of the object. Something with perfect elasticity would bounce back to 5 m (ignoring the reaction motion of the Earth). A real apple would primarily squash instead of bouncing. The coefficient of restitution tells how much the object will bounce. (see https://en.wikipedia.org/wiki/Coefficient_of_restitution )
 
  • #5
If there's no loss of energy due to rebounding or anything else, then yes, you are correct on both.
 

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 whenever an object exerts a force on another object, the second object exerts an equal and opposite force back on the first object.

What are the three components of Newton's Third Law?

The three components of Newton's Third Law are action, reaction, and interaction. The action is the initial force exerted by one object on another, the reaction is the equal and opposite force exerted back on the first object, and the interaction is the overall process of forces being exerted and reactions occurring.

How can Newton's Third Law be applied to everyday situations?

Newton's Third Law can be applied to many everyday situations, such as walking, pushing a door, or jumping. When you walk, your feet exert a force on the ground, and the ground exerts an equal and opposite force back on your feet, propelling you forward. Similarly, when you push a door, the door exerts a force back on your hand, allowing you to open it.

What is the mathematical equation for Newton's Third Law?

The mathematical equation for Newton's Third Law is F1 = -F2, where F1 is the force exerted by the first object and F2 is the force exerted by the second object. This equation shows the equal and opposite forces acting between the two objects.

How is Newton's Third Law related to conservation of momentum?

Newton's Third Law is related to conservation of momentum because the equal and opposite forces between two objects result in the conservation of momentum. This means that the total momentum of the two objects before and after the interaction remains the same, as the forces cancel each other out.

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