A rectangular bar with a cross section of width b and thickness c (where b is the longer side) is subjected to a torque T. Where does the maximum shearing stress occur?

Correct answer: In the middle of the longest side b.

Explanation

Unlike circular shafts where torsional shear stress is maximum at the outer radius, the stress distribution in rectangular bars is more complex. The maximum stress occurs at the midpoint of the longer sides, while the stress at the corners is zero.

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