Compressed spring momentum problem

AI Thread Summary
When a compressed spring between two carts is released, both carts experience equal momentum but move in opposite directions. The lighter cart travels further because it has a smaller mass, which results in a higher speed to maintain equal momentum. This relationship is described by the equation p = mv, where momentum (p) is the product of mass (m) and velocity (v). The greater speed of the lighter cart allows it to overcome friction more effectively than the heavier cart. Thus, the lighter cart's higher velocity compensates for its lower mass, enabling it to cover a greater distance.
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Homework Statement



Two lab carts, one heavy and one light, are placed ed to end with a large, compressed spring placed between the two carts. The spring is suddenly released. Describe the motions of the two carts after the spring is released.

Homework Equations

An equation isn't needed.



The Attempt at a Solution

The lighter of the two carts would go further right? Why is it that it goes further though, other than it simply being easier to push?
 
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Yes, the lighter cart will go further.
And you actually need an equation here: p = mv
They both get imparted with the same momentum, from the spring.
So why does one have a higher speed than the other?
 


Is it simply that the velocity must compensate for the smaller mass?
 


Yes, it has a higher speed because their momenta are equal (in opposite directions though). Since one mass is smaller, the speed has to be higher, so it will travel further before the force of friction stops it.
 
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