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soffish335
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Homework Statement
The Hubble Space Telescope is stabilized to within an angle of about 2 millionths of a degree by means of a series of gyroscopes that spin at 1.92×104 . Although the structure of these gyroscopes is actually quite complex, we can model each of the gyroscopes as a thin-walled cylinder of mass 2.00 and diameter 5.00 , spinning about its central axis.
How large a torque would it take to cause these gyroscopes to precess through an angle of 1.30×10−6 degree during a 5.00 hour exposure of a galaxy?
Homework Equations
L=I*ω
torque = Ω*L
I=mr^2
Ω=Δθ/Δt
The Attempt at a Solution
ω=1.92*10^4rpm
=2010.62rad/s
I=mr^2
=2(0.005)^2
=0.005
Δθ=1.3*10^6deg
=7.4484*10^-5rad
Δt=5 hours
=18000s
torque = Ω*I*ω
=(7.4484*10^-5/18000)*0.005*2010.62
=4.1*10^-8 Nm
This is the wrong answer and I feel as if the torque shold be rather larger by intuition. Any help would be appreciated.
Edit: 3.17*10^-12 Nm turned out to be the correct answer, but i'd still like to know how to do this question.
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