cq_1_201

phy 121

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: ->->->->->->->->->->->-> :

To keep the strap from rotating, the second rubber band will have to exert a force of 3 Newtons.

• 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 the glue comes loose, the strap will fly forward toward you!

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10 min

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&#This looks very good. Let me know if you have any questions. &#