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Tuesday, October 12, 2010
Ch8 2 #2
The "net torque" is the sum of all torques. Remember the opposite rotation directions have opposite signs.
3 comments:
Anonymous
said...
I tried finding t2-t1 however this was not the answer. What am I doing wrong?
The idea here is to use equation 8.10. Since tau=force * radius, just plug in half the diameter for the radius. You do not use sine or cosine here. Since clockwise is positive here, just take the difference between the two torques.
3 comments:
I tried finding t2-t1 however this was not the answer. What am I doing wrong?
For r, do we divide the number we're given (i.e. 4cm) in the drawing and have r=2cm=.002m?
The idea here is to use equation 8.10. Since tau=force * radius, just plug in half the diameter for the radius. You do not use sine or cosine here. Since clockwise is positive here, just take the difference between the two torques.
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