Kinetic Energy in Circular Motion: Is 1/2 m v^2 Still Applicable?

AI Thread Summary
In circular motion, the kinetic energy formula 1/2 m v^2 is applicable for point masses, such as those at the end of a massless string. For more complex objects, the moment of inertia and rotational kinetic energy must be considered. The kinetic energy is dependent on the speed squared, not the direction of travel, which is crucial in circular motion. For further understanding, exploring the concept of a "Physical Pendulum" is recommended. Overall, the applicability of the formula varies based on the object's characteristics.
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Homework Statement


in circular motion (e.g. a pendulum) is the kinetic energy still 1/2 m v ^2 or is it a different equation?

Homework Equations


1/2 m v ^2

The Attempt at a Solution

 
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It depends on what the object is. For a point mass at the end of a massless string you might use 1/2 m v^2. For a more complicated object that can't be viewed as a point mass you'll want to look at the moment of inertia and rotational kinetic energy. Investigate: "Physical Pendulum".
 
Just to add: for a point mass, the kinetic energy depends on the speed (##|\vec{v}|^2##) rather than the (vector) velocity, so the direction of travel (e.g. circular motion) doesn't matter.
 
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