cq_1_201

Phy231

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 situation here is similar to that depicted above, though the distances of the rubber bands from the center are different.

The die on which the strap rotates is not visible, but is attached to the tabletop; the blue push pin constrains the system

to rotate about a vertical axis through the center of the die.

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

2 least 3N

#$&*

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

The metal strap will come towards me holding the rubber bands.

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5min

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5/14/10 2pm

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

Solution

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