revolving force
revolving force
(OP)
if I have 1700 lbs. of perfectly balanced weight and apply a force of 20 ft.lbs. in torque for 5 sec. whats the ammont of counter torque and time needed to cause the weight to stop spinning. looking at storing energy in a revolving mass based on the yo-yo theory?
thanks
thanks





RE: revolving force
Cheers
Greg Locock
RE: revolving force
RE: revolving force
I'd personally don't recommend trying to stop rotating masses with hand held tools. If something catches you could be waving goodbye to one hand. (Waving with the other hand, obviously....!)
"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams
RE: revolving force
Your rotating mass has stored energy in it and you need to consume it: this is exactly the purpose of brakes.
prex
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RE: revolving force
"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams
RE: revolving force
RE: revolving force
To calculate the stored energy in your mass, you need to know the "moment of inertia" of that mass about its rotational axis and also the angular velocity of the mass after 5 seconds at this point the stored energy of the flywheel would be :-
K.E=1/2 x I x w^2
where K.E is the kinetic energy
I is the moment of inertia
w is the angular velocity
Further to this to find out how much torque required to stop it you need to consider the change in angular momentum
therefore T x t = I x (w1-w2)
where t = time required to stop the mass
T = Torque
I = moment of inertia
w1 and w2 are the initial and final angular velocities
of the mass (for stopping completely w2 = 0)
so you need to decide in what time you wish to stop the rotation and transpose the formulae to find T ie:-
T = I x (w1-w2)/(t)
hope this helps