# physics

a uniform disk of mass 3kg and radius 12cm rotates at 480 rev/min. find its kinetic energy (Hint : I of uniform disk =1/2MR2)

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1. KE=1/2 I w^2
angular speed= PI*rev/min*1min/60sec= 480*2pi/60= 50.3 rad/sec
I= 1/2 *3*.12^2=.0216 kg.m^2

KE=1/2 *I*w^2

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bobpursley
2. a uniform disk of mass 3kg and radius 12cm rotates at 480 rev/min. find its kinetic energy (Hint : I of uniform disk =1/2MR2)

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