Finding angular speed of a precessing gyroscope

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Fluxthroughme
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Handwritten working for a gyroscope precession problem: part a computes (0.025 + 0.14) x 9.81 = 1.614 N; part b converts 1 rev per 2.2 s to 60/2.2 = 27.27 rev/min; then rF = Ω_p I ω gives ω = 0.04 x 1.614 / (27.27 x 1.2 x 10^-4) = 19.79 rev/min.


Haven't done much work with gyroscopes, so I think I'm just missing something obvious, but since I'm using very basic formulas, I cannot see my error. The stated answer is [itex]1.8*10^3 rev/min[/itex], so I am clearly off.
 
Keep track of all of your units in your calculation. Note that using dL/dt = ΩpL requires Ωp to be in rad/s or rad/min (depending on your unit of time). I would suggest sticking with SI units throughout the calculation and then converting to rev/min at the end.
 
TSny said:
Keep track of all of your units in your calculation. Note that using dL/dt = ΩpL requires Ωp to be in rad/s or rad/min (depending on your unit of time). I would suggest sticking with SI units throughout the calculation and then converting to rev/min at the end.

Ahh! Converting to rad/s first and converting to rev/min at the end does work. So it WAS something simple :P Thank you!