Question

A cylinder of length L would be made to carry a torque T with an angle of twist ɸ. There are two options considered: 1) hollowed cylinder with an inner radius that is equal to 0.9 of the outer radius, and 2) solid cylinder (with a different radius). If both options would be made from the same material and must have the same angle of twist ɸ under the torque T, find the ratio of the weight between the cylinder designed for option 1 and option 2.

Answer 1

See explaination

Step-by-step explanation:

To compare the hollow and solid cylinder we need ro use torsional formula.

And since same material and length are given.

For same torque and angle of twist there will be same polar moment of area of the section for both the cylinder.

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