Under normal operating conditions, the electric motor exerts a 12-kip·in. torque at E. Kno...

Calculate the maximum shearing stress by using the following relation:

Here, is the maximum shearing stress in BC, is the torque exerted by the shaft BC, is the polar moment of inertia of the shaft BC, is the radius of the shaft BC.

Substitute for, for , for

Therefore, the maximum shearing stress at BC is

(b)

Consider shaft CD

Calculate the polar moment of inertia for the given shaft CD

Here, is the radius of the shaft CD.

Substitute, for .

Calculate the maximum shearing stress by using the following relation:

Substitute for , for , for

Therefore, the maximum shearing stress at CD is .

Consider shaft DE

Calculate the polar moment of inertia for the given shaft DE

Here, is the radius of the shaft DE.

Substitute, for .

Calculate the maximum shearing stress by using the following relation:

Substitute for , for , for

Therefore, the maximum shearing stress at DE is .