# Energy of translation compared to the energy of rotation

kuruman
Homework Helper
Gold Member
Judging from the title of this thread, "Energy of translation compared to the energy of rotation", I thought OP is asking that. The title indicates a comparison of how much of the input energy goes into translational and how much into rotational energy. Without knowing the ratio of the masses, this comparison is meaningless.

So the energy needed to rotate the pinion is d2*F1 = 94*1= 94 J. The energy needed to move the pinion in translation is lg*(sin(pi/4)-sin(pi/6))/(pi/12) = 103 J.
Please, correct that: So the energy needed to rotate the pinion is d2*F1 = 94*1= 94 J. The energy recovered from the pinion in translation is lg*(sin(pi/4)-sin(pi/6))/(pi/12) = 103 J. That calculation is not correct, just approxiative, I corrected in the message to have the true calculation.

I would like to study with the mass as lower as possible, mass-less is perfect. And the energy-in must be equal to the energy-out.

Even there are external devices to control the position, the sum of energy in that devices are constant, I supposed the external devices perfect, again to simplify the calculations.

jbriggs444