Kinetic energy of two moving objects

AI Thread Summary
The discussion centers on the kinetic energy of two objects in motion relative to each other. When a mass m moves towards a stationary mass M, its kinetic energy in the reference frame of M is calculated as 1/2mV^2, while M's kinetic energy in the reference frame of m is 1/2MV^2. The difference in kinetic energy between the two bodies is expressed as 1/2(M-m)V^2. Participants debate whether this difference in kinetic energy is a meaningful quantity in understanding their interaction. The conversation highlights the complexities of analyzing kinetic energy from different reference frames.
malemdk
125
11
Assume a body of mass m moving with velocity V1 towards a body with a mass M and its velocity is zero
The kinetic energy of the first body with respect to the second body is 1/2mV2 in the reference frame fixed to the non moving body
The kinetic energy of the second body with respect to the first body is 1/2MV2 in the reference frame fixed to the moving body

There is difference in KE 1/2(M-m)v^2
 
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malemdk said:
There is difference in KE 1/2(M-m)v^2
Do you think that is a meaningful quantity?
 

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