ezzieyguywuf
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I have the 2016 NCEES practice exam for Machine Design and Materials. Problem 112 shows a horizontal shaft that is cantilevered on the left. On the right, there is a spring between the shaft and a wall. The problem is to determine the "increase in force" due to a change in temperature. The young's modulus, cross-section, and coefficient of thermal expansion are given for the shaft and the spring constant is given for the spring.
My original solution for this looks something like this:
However the solution in the text begins with something like this:
I can see how Hooke's law can be used to relate the spring constant to the Young's Modulus:
But the rest of their solution makes no sense to me. Why does the RHS of their equation subtract the spring deflection from the thermal expansion?
My original solution for this looks something like this:
However the solution in the text begins with something like this:
I can see how Hooke's law can be used to relate the spring constant to the Young's Modulus:
But the rest of their solution makes no sense to me. Why does the RHS of their equation subtract the spring deflection from the thermal expansion?
