1) The pulley on an Atwood machine has a moment of inertia of 5.0 KG and a radius of .5 meters. The cord supporting the masses does not slip and the axle is frictionless. (A) Find the acceleration of each mass if M1 = 2Kg and M2 = 5Kg. (B) Find the tension in the cable supporting M1 and the tension in the cable supporting M2.(adsbygoogle = window.adsbygoogle || []).push({});

My Analysis:

Obviously M2 is going to accelerate it down. M1 and the Pulley are what is resisting the pull. I know this but am having a hard time wiht how to set up the formula to solve it.

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2) A model airplane whose mass is .75 KG is tethered by a wire so that it flies in a circle 30 meters in radius. The airplane engine provides a net thrust of .8 newtons perpendicular to the tethering wire. (A) Find the torque the net thrust produces about the center of the circle. (B) Find the acceleration oif the airplane when it is in level flight. (C) Find the linerar acceleration of the airplane tanget to its flight path.

My Work:

I got part A and C correctly-

A) 24 N/m

C) 64 Rad/s

Again I am confused on what exactly they are asking for in part B, and am confused with what formula to use. I originally thought it would be the tangential acceleration added to the centripetal acceleration, but it came off way wrtong. The answer comes out to be .0356 Rad/s, but again, I cannot figure it out.

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# Homework Help: Two Extra Credit Rotation Questions

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