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3 years ago

10

Maximum iorsional shear siress.? Select one: a)- occurs at the center of a shaft. b)- occurs at the outer surface of a shaft c)-

occurs at the inner surface of a shaft.

1 answer:

pickupchik [31]3 years ago

4 0

Answer:

b). Occurs at the outer surface of the shaft

Explanation:

We know from shear stress and torque relationship, we know that

$\frac{T}{J}= \frac{\tau }{r}$

where, T = torque

J = polar moment of inertia of shaft

τ = torsional shear stress

r = raduis of the shaft

Therefore from the above relation we see that

$\tau = \frac{T.r}{J}$

Thus torsional shear stress, τ is directly proportional to the radius,r of the shaft.

When r= 0, then τ = 0

and when r = R , τ is maximum

Thus, torsional shear stress is maximum at the outer surface of the shaft.

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