- #26

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I've been doing a lot of homework on this....

...I re-read the part on shear stresses on beams from my book and I think the most important part would be where it says

Now, coming to the second part of my post#24, I wrote:

...now, in my book,

...I re-read the part on shear stresses on beams from my book and I think the most important part would be where it says

*"the ementary normal and shearing forces exerted on a given transverse section of a prismatic beam with a vertical plane of symmetry are equivalent to the bending couple M and the shearing force V"*(where V and M would be the Vc and Mc on the diagrams you attached).**So now I understand that the moment Mc as per your diagram is not caused***directly*by an applied load...but its a result of the distribution of shear stresses produced when there is an applied load.Now, coming to the second part of my post#24, I wrote:

"....how Ma and Mb in a fixed beam can be different values if there is indeed a pair of equal and opposite forces (denoted by 'R' in the diagram that I took from the book- post #15 on the other thread) that is responsible for them... ""....how Ma and Mb in a fixed beam can be different values if there is indeed a pair of equal and opposite forces (denoted by 'R' in the diagram that I took from the book- post #15 on the other thread) that is responsible for them... "

...now, in my book,

**they have an equation that goes Mb-Ma=RL**(referring to my earlier diagram showing the two forces 'R'...L is the length of the beam).....**also, I found that in case of symmetrical loading, the end moments (Ma and Mb)are equal but this leads to the fact that R=0**.....__so I guess that 'R' is not the only fixed end reaction that causes the bending moments__.....so in the case of symmetrical loading(say with load at centre point),*there is also some other force that produces the end moments Ma and Mb*....**is this even remotely correct?**
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