mechanics ii mech 220

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0ctober 12, 2005

10:30 to 11:30

8losed book, one 8.5 in x 11 in sheet allowed, double sides 1.023"! 4

54+ m7r9s;

A motorcycle Cof total mass 140 kg with the riderG starts from rest at t H 0 and moves along a circular track with 400-m radius. The tangential component of its acceleration is, in mLs2: at " 2 ! 0.2t At time t H 12.36 seconds, friction can no longer keep it on the circular track and it spins out. CaG How fast is it going at this timeO CbG Phat is the magnitude of its acceleration at this timeO CcG Qketch the speed vs. time profile of the motorcycle for the time till spin out.

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R15 marksS

The illustrated pulley system is released from rest. How much time is needed for 0 to contact the groundO mA H 20 kg and mT H 160 kg. The pulleys and ropes are massless.

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1.023"!