Kinetic rotational energy problem

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Homework Help Overview

The problem involves a diatomic molecule modeled as two point masses and examines its kinetic energy when rotating about different axes. The context is within the subject area of rotational dynamics.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to analyze the kinetic energy of a diatomic molecule when rotating about the x-axis, z-axis, and y-axis, considering the moment of inertia and the perpendicular distances from the rotation axes.

Discussion Status

Some participants affirm the original poster's reasoning, while others suggest that the poster should develop their own methods for evaluating the correctness of their answers. The discussion reflects a mix of validation and encouragement for self-assessment.

Contextual Notes

The original poster's reasoning includes assumptions about the moment of inertia and the distances involved in the kinetic energy calculations, which may require further exploration or clarification.

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.
 

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