cq_1_201

PHY 201

Your 'cq_1_20.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

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The problem:

The metal strap used in the Angular Velocity of a Strap experiment is constrained by a vertical push pin to rotate about a hole in a die. The die is glued in place to a massive tabletop. A rubber band is attached to a point 15 cm from the axis and stretched so that it exerts a force of 3 Newtons, directed perpendicular to the rod. If this force is unopposed it will accelerate the system rapidly. You want to attach a second rubber band 5 cm from the axis to prevent the system from rotating.

• How much force will that rubber band have to exert?

answer/question/discussion: ->->->->->->->->->->->-> :

If the rubber band that is placed at the 15 cm mark will exert a force of 3 N, another rubber band placed at the 5 cm mark going in the opposed direction will exert a force less force, because it is more towards the center of the rotation.

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• Once both of these forces are in place and the system is stationary, what (if anything) will happen if the glue holding the die to the tabletop comes loose?

answer/question/discussion: ->->->->->->->->->->->-> :

If you opposing forces and not wanting the blade to rotate, then it will matter at all if the die comes loose from the table or not.

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20 minutes

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Solution

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