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hello, i just started following your work few days ago and I was learning to build this project by following your steps but my shear force diagram doesn’t end back at zero on y axis, can you please help me with what the possible error might be? thanks!
Your diagram isn’t incorrect - rather, it is implied that the right-hand reaction will reduce the shear force back down to zero at the right hand support.
If you wanted to represent this on the diagram, you would need to plot a vertical line on the diagram since a point load introduces a step-change in the SFD (i.e. a line with both ends having the same x-coord).
Seán
Oh I understand it now! thank you so much for your swift explanation!