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## Main Question or Discussion Point

Hi,

on the net I found some equation, and would like to know if they are correct ones.

http://www.upei.ca/~physics/p261/projects/flywheel1/flywheel1.htm

http://hyperphysics.phy-astr.gsu.edu/hbase/rke.html

But I searched for that "I" (inertia momentum) on the Wiki http://en.wikipedia.org/wiki/Moment_of_inertia and there is not like it say above "I=k*m*w2"

on the net I found some equation, and would like to know if they are correct ones.

http://www.upei.ca/~physics/p261/projects/flywheel1/flywheel1.htm

http://hyperphysics.phy-astr.gsu.edu/hbase/rke.html

*Physics:*

Stored energy = sum of kinetic energy of individual mass elements that comprise the flywheel

Kinetic Energy = 1/2*I*w2 , where

I = moment of inertia (ability of an obeject to resist changes in its rotational velocity)

w = rotational velocity (rpm)

I = k*M*R2 (M=mass; R=radius); k = inertial constant (depends on shape)

Inertial constants for different shapes:

Wheel loaded at rim (bike tire); k = 1

solid disk of uniform thickness; k = 1/2

solid sphere; k = 2/5

spherical shell; k = 2/3

thin rectangular rod; k = 1/2Stored energy = sum of kinetic energy of individual mass elements that comprise the flywheel

Kinetic Energy = 1/2*I*w2 , where

I = moment of inertia (ability of an obeject to resist changes in its rotational velocity)

w = rotational velocity (rpm)

I = k*M*R2 (M=mass; R=radius); k = inertial constant (depends on shape)

Inertial constants for different shapes:

Wheel loaded at rim (bike tire); k = 1

solid disk of uniform thickness; k = 1/2

solid sphere; k = 2/5

spherical shell; k = 2/3

thin rectangular rod; k = 1/2

But I searched for that "I" (inertia momentum) on the Wiki http://en.wikipedia.org/wiki/Moment_of_inertia and there is not like it say above "I=k*m*w2"