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

A solid circular shaft has a diameter of 200mm. What would be the dimension of a hollow

shaft which could replace it (i.e. transmit the same torque for the same maximum shear

stress), and what would be the percentage reduction in the material required? The internal

and external diameters of the hollow shaft are to be in the ratio of 4:5. (Ans: 23.84 cm,

19.07 cm; 48.9%)

2. Relevant equations

T/J = G(theta)/L = tao/R

J = pi(d)^4/32

3. The attempt at a solution

J = pi(0.2)^4/32 = 0.000157

pi(5d)^4/32 - pi(4d)^4/32 = 0.000157

d = 0.2m

5d = 1m (wrong)

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# Homework Help: Equivalent torque of hollow shaft

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