Physics Help Forum angular motion

 Periodic and Circular Motion Periodic and Circular Motion Physics Help Forum

 Nov 19th 2010, 10:59 AM #11 Physics Team     Join Date: Jun 2010 Location: Mauritius Posts: 609 Oh you're right, I placed the '2' inside the brackets while it should be outside. WD = F.s WD = Fr(theta) T = Fd; d = 2r, so, T = 2Fr, and F = T/(2r) Pt = (T/2) x angular displacement T = (Pt x 2)/angular displacement = (5000 * 300 * 2)/1200pi = 796 Nm __________________ Jerry (Got my results!) It is easier to protect your feet with slippers than to cover the earth with carpet. No one can go back and change a bad beginning; but anyone can start now and create a successful ending. If a problem can be solved, no need to worry about it. If it cannot be solved what is the use of worrying?
Nov 30th 2010, 06:20 PM   #12
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Join Date: Nov 2010
Location: Clarksville, AR
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 Originally Posted by Unknown008 e) I would think that on the motor, there are two ropes acting on it, and hence, the torque is Fd where d is the diameter... =/ Then, in this line: You used the angular velocity instead of the angular displacement and the radius instead of the diameter. Torque = 1500000/(1200pi * 2) = 796 Nm Using what I was saying, v = r(omega) = 0.15 * (120*2pi/60) = 3pi/5 5000 = F(3pi/5) F = 2650 N Fd = T T = 2650 x 0.3 = 796 Nm
Two ropes???

For constant speed, v, P=Fv.

For constant angular velocity, P=(torque)(angular velocity).