Torsion question can anyone help?

[scw1]

Torsion question can anyone help?

Homework Statement

For a power transmission system, a solid steel shaft is required to transmit a torque of 2000 Nm. The limiting factor is that the twist of the shaft should not exceed 5 degrees for each metre of the shaft length. The shear modulus G is 75 GPa for this steel. What should be the minimum shaft diameter??

Homework Equations

The general bending formula
T/J=Tau/r=Gxtheta/L

The Attempt at a Solution

I tried to use the bending formula and come up with 14mm minimum diameter shaft

 

[rock.freak667]

The Attempt at a Solution

I tried to use the bending formula and come up with 14mm minimum diameter shaft

Your equation is the torsion equation, but could you post your working, I don't have a calculator on hand to check your answer.

 

[nvn]

scw1: Your equation in post 1 is correct, but your current answer is incorrect. Ensure you are using correct units, and ensure you are using the correct equation for J. Try again.