Calculate RPM: Kinetic Energy of a Wheel with Mass 15kg and Diameter 1.2m

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To calculate the RPM of a wheel with a mass of 15 kg and a diameter of 1.2 m, the radius of gyration is used to determine the moment of inertia (I), which is 2.4 kgm². The kinetic energy (KE) formula is applied, where KE = 0.5 Iω², and ω is expressed in terms of RPM. The wheel's linear speed of 4 m/s is considered, leading to the need to determine how far the wheel travels in one revolution. The discussion emphasizes the importance of understanding both rotational and linear kinetic energy for a rolling wheel. Ultimately, the calculation of RPM is essential for finding the total kinetic energy of the wheel.
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1. I need to find out the kinetic energy of a wheel, mass 15kg, diameter 1.2m, radius of gyration 0.4m traveling at 4ms. To do this I need to find RPM



2. Kinetic Energy = 0.5 Iw^2, I = mk^2



3. I = 15 x 0.4^2 = 15 x 0.16 =2.4kgm^2

KE = 0.5 x 2.4 x w^2

W = rpm x 2pi/60
How can I find rpm
 
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Hi Kev1n! :smile:

(have an omega: ω and try using the X2 tag just above the Reply box :wink:)
Kev1n said:
I need to find out the kinetic energy of a wheel, mass 15kg, diameter 1.2m, radius of gyration 0.4m traveling at 4ms. To do this I need to find RPM

How can I find rpm

Is this a rolling wheel?

If so, it will have both rotational kinetic energy and ordinary kinetic energy.

And the speed is 4 m/s, and the diameter is 1.2m, so how far does the wheel move when it goes round one revolution? :smile:
 
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