A solid ball - kinetic energy and angular speed

AI Thread Summary
The discussion focuses on calculating the kinetic energy of a solid ball with a mass of 1.30 kg and a diameter of 19.0 cm, rotating at 65.0 revolutions per minute. The formula for rotational kinetic energy, KE = 1/2 I ω², is highlighted, where I is the moment of inertia and ω is the angular velocity. It is noted that for a solid sphere, the moment of inertia is I = 2MR²/5. Additionally, the conversion of revolutions to radians is questioned, emphasizing the need for this conversion in calculations. The conversation aims to determine both the initial kinetic energy and the new angular speed after supplying an additional 2.60 J of energy.
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A solid ball of mass 1.30 kg and diameter 19.0 cm is rotating about its diameter at 65.0 rev/min.

What is its kinetic energy?

Also, if an additional 2.60 J of energy are supplied to the rotational energy,

what is the new angular speed of the ball?
 
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Rotational kintic energy is given by

{KE = \frac 1 2 I \omega^2

Where I is the moment of initera and \omega= angular velocity.
 
Thanks alot

That doesn't help any
 
Were you given that, for a solid sphere, I=2MR2/5 ?

How many radians are there in a revolution?
 

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