cq_1_201

Phy 231

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 system from rotating, you would have to do equal and opposite force. It sounds as if the first rubber band is already doing 3 N of force, so to prevent the system from rotating, this second rubber band will also have to do 3 N of force.

• 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 die was to come unhinged, then, based on the picture, I would assume that the metal strap will be propelled towards the force of motion.

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15 min

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&#Please compare your solutions with the expanded discussion at the link

Solution

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