Calculating the shear and moment diagrams of a beam with a hinge

[DS5555]

Homework Statement

I am given a beam fixed to the wall at the left hand of the beam and supported by a pin on the righthand side. The pin is 3a long, and going from left to right there is a hinge at measure a into the beam, a distributed force w from a to 2a, and a moment of wa^2 being applied at the pin support. I have drawn out the shear moment diagram but I am struggling to understand how to draw the moment diagram, as the numbers from my shear force diagram don't seem to match the last segment of the moment diagram and I am confused on how to

Relevant Equations

M' = V
area = V'

 

[Lnewqban]

Welcome, DS5555!

What makes the value of the moment applied to the pin point change from right to left?

 

[DS5555]

Thank you! Happy to be here. I had read previously that the moment at the pin would be zero. Is this not true? For my thinking from the right side of the beam to the pin point, I see that I have a counter clockwise moment of 1 (assuming that the units are in wa^2 for simplification of the graph. My graph has the error of some of the values there being written with wa^2 instead of without) so I have to be at the end at positive 1. I then see that I have an area of 3/4wa^2, so In order to reach 1 I have to start at 1/4, and so then I draw a curve with the highpoint being at where the intersection is on my shear graph.