torque, angular acceleration

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Xavipersonal

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question -- You are an astronaut onboard the Space station. A satellite with
is Iz=1200kgm^2 rotating along is z-axis, which is pointing directly towards you. The satellite is slowly coming towards you. It has a steady rotation about its z-axis of OMEGAz=0.1rad/s. The satellite has handles on its surface mounted 0.5 m from its centre of gravity.
How much force should you apply altogether on the handles to stop the
rotation within 2 seconds?

That was the question. I solved it knowing that Iz=m*r^2 and mass is 4800 kg
and I also got the centripetal acceleration a=-OMEGA^2 * r =5e-3 m/s2 but my
problem is that I cannot see the relation with the time in this question.

Thank you very much in advance
 

Remember τ = I dω/dt (Torque = M_inertia · angular_acceleration)

Then τ = F/d = I Δω/Δt because the angular acceleration is constant

==> F = d I ω / t (ω final is 0)
F = .5 1200 .1 / 2 = 30 N
 

Thanks you very much Eduardo it has been really useful answer
 

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