Help with shear stress and angle of twist

AI Thread Summary
The discussion revolves around calculating the maximum shear stress and angle of twist for a solid shaft with a diameter of 100mm, transmitting 75kW at 150 rev/min. The user has calculated the shear stress as 2.4 mNm² but is uncertain about finding the angle of twist without the shaft length. There is confusion regarding the units for stress, as one participant notes unfamiliarity with 'mNm².' To assist further, additional calculations or work details are requested from the original poster. The conversation highlights the importance of having all necessary parameters for accurate mechanical calculations.
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A solid shaft 100mm diameter which transmits 75kw at 150 rev/min.

the question is asking me to find the max shear stress and angle of twist per metre of the shaft length.

G=80GN/m^2

I was under the impression to find the angle of twist you needed the length in the first place. None of the examples in class had length missing.
I worked the shear stress out as 2.4mNm^2

Thanks for any help
 
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ball said:
A solid shaft 100mm diameter which transmits 75kw at 150 rev/min.

the question is asking me to find the max shear stress and angle of twist per metre of the shaft length.

G=80GN/m^2

I was under the impression to find the angle of twist you needed the length in the first place. None of the examples in class had length missing.
I worked the shear stress out as 2.4mNm^2

Thanks for any help

"the question is asking me to find the max shear stress and angle of twist per meter of the shaft length."

I'm unfamiliar with units of 'mNm^2' for stress.

Anywho, if you want any help on this question, you need to provide some of your work.
 
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