What is the kinetic energy of the center of mass

AI Thread Summary
The discussion centers on calculating the kinetic energy of the center of mass for two 0.50-kg carts pushed toward each other on a low-friction track. Participants emphasize the importance of determining the center of mass position and total momentum vector to find the kinetic energy accurately. Initial calculations suggest a misunderstanding of how to find the speed of the center of mass, leading to incorrect results. The position of the center of mass is initially identified as 3 m, but further clarification is needed on its position after a short time. Accurate calculations hinge on understanding the dynamics of the system and the forces applied to the carts.
emily081715
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Homework Statement


Two 0.50-kg carts are pushed toward each other from starting positions at either end of a 6.0-m low-friction track. Each cart is pushed with a force of 2.9 N , and that force is exerted for a distance of 1.0 m.
What is the kinetic energy of the center of mass of the system?

Homework Equations



=1/2mvcm^2

The Attempt at a Solution


1/2(0.5)(2.4/6.0)
=0.04
i don't know how to find speed so i know this is wrong
 
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Where is (what is the position of) the center of the mass at the beginning?
(It might help to find the total momentum vector of the system.)
 
robphy said:
Where is (what is the position of) the center of the mass at the beginning?
(It might help to find the total momentum vector of the system.)
i'm not sure, wouldn't it just be 3 m
 
Where is the center of mass (say) 0.1s later?
 

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