A shaft made of stainless steel has an outside diameter of 42 mm and a wall thickness of 4 mm. Determine the maximum torque T that may be applied to the shaft if the allowable shear stress is equal to 100 MPa.

Respuesta :

Answer:

Explanation:

Using equation of pure torsion

[tex]\frac{T}{I_{polar} }=\frac{t}{r}[/tex]

where

T is the applied Torque

[tex]I_{polar}[/tex] is polar moment of inertia of the shaft

t is the shear stress at a distance r from the center

r is distance from center

For a shaft with

[tex]D_{0} =[/tex] Outer Diameter

[tex]D_{i} =[/tex] Inner Diameter

[tex]I_{polar}=\frac{\pi (D_{o} ^{4}-D_{in} ^{4}) }{32}[/tex]

Applying values in the above equation we get

[tex]I_{polar} =\frac{\pi(0.042^{4}-(0.042-.008)^{4})}{32}\\

I_{polar}= 1.74[/tex] x [tex]10^{-7} m^{4}[/tex]

Thus from the equation of torsion we get

[tex]T=\frac{I_{polar} t}{r}[/tex]

Applying values we get

[tex]T=\frac{1.74X10^{-7}X100X10^{6}  }{.021}[/tex]

T =829.97Nm