(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

To get a flat, uniform cylindrical satellite spinning at the correct rate, engineers fire four tangential rockets as shown in the figure. If the satellite has a mass of 3600 kg, a radius of 4.6 m, and the rockets each add a mass of 230 kg, what is the required steady force of each rocket if the satellite is to reach 33 rpm in 5.3 min, starting from rest?

2. Relevant equations

moment of inertia for point masses (rockets) and cylinder (satellite) and torque and rotational kinematics

3. The attempt at a solution

So i first convert 33 rpm to 3.455 rad/s and 5.3min to 318s. Next I use the equation [tex]\omega[/tex] = [tex]\alpha[/tex] t and solve for [tex]\alpha[/tex]. I get 0.1086 rad/s/s. then for the moments of intertia, I get 0.5 * (mass of rocket) * (radius)^2. I also get 4 * (mass of satellite) * (radius)^2. I added those together to get the total moment of inertia which is 38402.64 kg*m^2. To get the torque I multiply the total moment of inertia and the angular acceleration I found earlier and get 625N then divide by 4 for each rocket and get 156N. The program says this answer is wrong, but I dont see where the fault lies.

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# Homework Help: Satellites rockets and torque

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