Kinetic rotational energy problem

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spaghetti3451
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Homework Statement



A diatomic molecule can be modeled as two point masses, m1 and m2, slightly separated. If the molecule is oriented along the y-axis, it has kinetic energy K when it spins about the x-axis. What will its kinetic energy (in terms of K) be if it spins at the same angular speed about

(a) the z-axis
(b) the y-axis?

Homework Equations



K = 0.5Iω2

The Attempt at a Solution



(a) I stays the same as the atoms are the same perpendicular distance from the origin. So the kinetic energy = K.

(b) I = 0 as the perpendicular distance between each atom and the rotation axis (the y-axis) is 0. So, kinetic energy = 0.

It would help me if you comment on my solution.
 
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Looks good to me.
Was there anything in particular you were concerned about?
 
Oh no, just wanted to know if my answers were good. Thanks, by the way!
 
No worries.
Looks like you need to develop ways to decide for yourself if your answers are good.