Engineering Solid Mechanics Beam Stress Question

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To solve the beam stress problem, the singularity function is used to express the moment as a function of x, leading to deflections calculated by integrating the moment equation twice. The equation to apply is EI d²y/dx² = M(x). It's important to include a constant moment in M(x), which may have been overlooked, as well as considering vertical reactions and moments at point A for equilibrium. The discussion also notes a mix-up with uploaded solution attempts. Accurate formulation of the moment and shear stress is crucial for proper analysis.
Leighanne
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Homework Statement
Looking for some help in solving this practice problem, I have tried multiple times and can't seem to get to the correct answers.
Relevant Equations
The solid 30 mm diameter steel [E = 200 GPa] shaft shown in Figure supports two pulleys. For the loading shown, use discontinuity functions to compute:

(a) the deflection of the shaft at pulley B.

(b) the deflection of the shaft at pulley C.

answers: (1.539mm, 6.15mm)
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You are supposed to use the singularity function to find the deflections. You need to write the moment as a function of ##x##. Then the deflections come from integrating twice:

$$EI \frac{d^2y}{dx^2} = M(x)$$

Why are you trying to find the shear stress?
 
Uploaded the wrong solution attempt whoops!
heres the correct one.
1704650460080.png
 
Leighanne said:
Uploaded the wrong solution attempt whoops!
heres the correct one.
View attachment 338230
There should be a constant moment that you have not included in ##M(x)##. There may be more, but start there( i.e there is vertical reaction and moment at A under equilibrium).
 
I have a question that I couldn’t fully understand its logic. The professor asked us to calculate the shear resistance and moment about the X and Y axis, using the given cross-section and the values of compressive and tensile stresses. I understand how to get the moment, but I’m confused about how to find the shear resistance from these stresses. Could you explain or clarify the method?

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