Recent content by elkedoring

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    Calculating Rotational Kinetic Energy of a Clock's Hands

    Thank you! I hadn't taken the 1/2 into consideration! That solves it!
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    Calculating Rotational Kinetic Energy of a Clock's Hands

    [SOLVED] Energy in Rotational Motion There is a clock that has an hour hand 2.7m long with a mass of 60 kg. The minute hand is 4.5m log with a mass of 100 kg. What is the total rotational kinetic energy assuming the hands act as long thin rods? K=I*rotation vel.^2 I=(1/3) ML^2 ( I think...
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    Rigid Object Under Torque: Solving for Time and Number of Revolutions

    Thank you that solved the problem!
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    Rigid Object Under Torque: Solving for Time and Number of Revolutions

    A grinding wheel is in the form of a uniform solid disk of radius 7cm and mass 2kg. It starts from rest and accelerates uniformly under the action of the constant torque of 0.6 Nm the motor exerts on the wheel. a) How long does the wheel take to reach its final operational speed of 1200 rev/min...
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    How High Does the Tennis Ball Rebound After Elastic Collision?

    That was a perfect hint! I've figured it out now. I just didn't have a sign in the right place so it screwed up the rest of the problem. Thank you so much!
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    Confusing System of Masses Question

    Ok, I think I can help get you started on this one. For ease I'm calling the 1kg block m1 and the .5kg block m2. First think I would do is consider the equation fs= us*N where fs is the force of friction, us is the coefficient of friction and N is the normal force on the block. So, for m1 you...
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    How High Does the Tennis Ball Rebound After Elastic Collision?

    [SOLVED]Elastic Collosions- help please? 1. A tennis ball of mass 57g is held just above a basketball of mass 590g. With their centers aligned, both are relesed from rest at the same moment, to fall 1.2m. a)Find the magnitude of the downward velocity of the basketball as it reaches the ground...