Talk:Mechanics of materials/Problem set 3

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An anonymous user edited the resource with the following claim. It was unsigned and not attributed. I am moving the comment here, as a claim like this in the resource itself can be unnecessarily confusing. I debated whether or not to leave a note in the text. At this point, I would prefer that the author of this resource comment. General policy would be to find consensus on a text. Simply claiming that something is wrong is not enough. The edit was to the solution for Problem 3.4:

This solution is incorrect. The largest possible solution should be found using the strength and size of the sleeve, not of the spindle

This "correction" appears incorrect (or incomplete) to me, because the torque could shear the spindle while the sleeve remains intact. The solution in the text appears incomplete to me, because there is no analysis of the strength of the sleeve, and the sleeve could shear while the spindle remains intact. So the largest possible torque without failure would consider the weakest part, and I don't know that without doing the math, which is not shown in the solution text. @Marshallsumter:, will you look at this? --Abd (discusscontribs) 00:14, 7 October 2017 (UTC)[reply]

Take a look at User:Jshminer46/Mom-s13-team4-R3, Problem set 3, Problem 3.4. This user analyzes both the sleeve and the spindle. Assuming the spindle is attached to the sleeve, and the torque is applied to the spindle. The maximum torque can be applied to the sleeve, but the problem applies the torque to the spindle. The spindle will yield before the sleeve so the maximum torque that can be applied is that of the weakest component - the spindle. The solution is correct as stated but the problem could be better explained by including the sleeve analysis performed by User:Jshminer46. What do you think? --Marshallsumter (discusscontribs) 03:04, 7 October 2017 (UTC)[reply]
Yes. Kudos to the IP for noticing what was missing, but the IP did not think it all the way through. Jshminer46 did, so congratulations to that user, who should be credited. --Abd (discusscontribs) 14:36, 7 October 2017 (UTC)[reply]