Total Kinetic Energy: Man, Globe, Platform

AI Thread Summary
The discussion centers on calculating the total kinetic energy of a system involving a man, a globe, and a turntable. The relevant equations for kinetic energy include K = 0.5Mv^2 for the globe and L^2/(2I) for the platform. The user attempts to compute the total kinetic energy, arriving at a value of 3.091 J. There is uncertainty about the correctness of the calculations, particularly regarding the equations used. The consensus suggests that the approach appears correct, providing reassurance to the user.
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Homework Statement


A man stands at the center of a turntable that can rotate without friction. He then takes a 1.5 kg globe of the Earth and swings it around his head at the end of a 0.7 m long chain. The world revolves around him every 3.4 s, and the man and the platform have a moment of inertia of 0.5 kgm^2. The angular velocity is 2.71 rad/s in the opposite direction to that of the globe. What is the total Kinetic Energy of the man, the globe, and the platform?

Homework Equations


K = 0.5Mv^2 of the globe + L^2/(2I) of the platform

The Attempt at a Solution


K total = 0.5Mv^2 + L^2/(2I)
K total = 0.5(1.5)(0.7x2pi/3.4)^2 + (0.5x2.71)^2/(2x0.5) = 3.091J

Plz. help... I do not think my answer is right... mainly the equation part...
-Thanks a lot...
 
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Looks right to me.
 

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