Kinetic energy in rotating objects.

Thread starter Duely Cack
Start date Oct 13, 2008
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Energy Kinetic Kinetic energy Rotating

AI Thread Summary

To calculate the kinetic energy of a rotating object, the formula K_e = 1/2 I ω² is used, where I is the moment of inertia and ω is the angular velocity in radians per second. For a 75-g phonograph album with a diameter of 30 cm spinning at 33.3 rpm, the mass must be converted to kilograms. The angular velocity can be calculated from rpm to radians per second. The discussion emphasizes the importance of using the correct units for mass and angular velocity in the kinetic energy formula. Understanding these conversions is crucial for accurate kinetic energy calculations in rotating objects.

Oct 13, 2008

Duely Cack

1. A 75-g phonograph album of 30-cm diameter spins at 33.3 rpm. What is its kinetic energy?

2. 1/2mv²

3. well i think that kinetic energy is 1/2mv² so is it like that but instead of v you put in the 33.3 rpm. like 1/2(75)(33.3)² maybe?

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Oct 13, 2008

Rake-MC

K_e = \frac{1}{2}I\omega^2

You have to use omega as radians per second, mass has to be in kilograms.

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