Can a Strong Man Push Two Freight Cars at Different Speeds?

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The strong man cannot push the two freight cars apart at different speeds due to Newton's third law, which states that for every action, there is an equal and opposite reaction. When he pushes one car, the other car acts as a brace, resulting in equal forces applied to both cars. Therefore, both cars will experience the same acceleration and speed. The discussion also touches on the relationship between force, mass, and acceleration, emphasizing that differing masses would result in different accelerations if the same force were applied. Understanding these principles is crucial for grasping the mechanics of the scenario.
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Homework Statement


The strong man will push the two initially stationary freight cars of equal mass apart before he himself drops straight to the ground. Is it possible for him to give either of the cards a greater speed than the other? Why or why not?

Homework Equations


None this is a theory question.

The Attempt at a Solution


It is not possible for the strongman to push either of the cars with a greater speed than the other because when the man pushes against one car, he is using the other car as a brace. So the force of the man pushing on one car would create a reaction force against the second car.

I am not really sure this is the right answer. I don't completely understand this concept about action and reaction forces yet.
 
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lynaa said:
So the force of the man pushing on one car would create a reaction force against the second car.

.

That part is right.

Is the "reaction" force on the second car equal in magnitude to the force on the first car?
 
rude man said:
That part is right.

Is the "reaction" force on the second car equal in magnitude to the force on the first car?

I think it should be because of Newton's third law? Or do I not understand how his law works as well?
 
lynaa said:
I think it should be because of Newton's third law? Or do I not understand how his law works as well?
Correct.
Now, if the same force magnitude is applied to objects of differing mass, would you expect them to move with the same magnitude of acceleration?
 
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