A 4 kg mass is connected by a light cord to a 3 kg mass on a smooth surface.The cord is around a frictionless axle and has a moment of inertia of .5 kg*m^2 and a radius of .3m. Assuming that the cord does not slip arount the axle,(adsbygoogle = window.adsbygoogle || []).push({});

a) what is the acceleration of the two masses

b)what are the forces of tension in the rope that connects to the two masses

I began this problem using the principle that if, as the first question shows, there is acceleration, then torque net is not equal to zero. In such a situation, the following equation is recommended:

moment of inertia* angular acceleration= sum of the torques. The equation for torque is force*distance from axis.

Apparently in such a problem, the torque net equation above must be supplemented with force net equations for each of the two masses. The force net equation is:

Force net *linear acceleration= sum of forces

By substituting the unknowns in the force net equation into the torque net equation, one should be able to find the acceleration and then the two forces.

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# Torque net

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