having some major issues with this unit, mainly since the homework was assigned and we haven't been lectured on it yet...so it's new to me. anyway, if anyone can help me out with this problem, that'd be awesome.(adsbygoogle = window.adsbygoogle || []).push({});

-----A helicopter rotor blade can be considered a long thin rod. If each of the three rotor helicopter blades is L = 3.85m long and has a mass of m = 158kg, calculate the moment of inertia of the three rotor blades about the axis of rotation.

How much torque must the motor apply to bring the blades up to a speed of 5.28 revolutions per second in 8.83s? --------

The inertia equation I found for this problem is I= 1/3 ml^2.....but i wasn't sure if i calculate this for each blade or just once. And also, I don't know what the units are. The second part of the problem, T=Fl.....so (3.85) (158)(9.8) = 5961.34 N*m....but how do i calculate bringing the bladed up to the given speed in a certain amount of time? Thanks for any help.

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# Moment of inertie of rotor blaes of a helicopter

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