Is Shear Force Always Maximum When Moment is Zero?

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chetzread
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Homework Statement


in the book , i was told that when the shear force is 0 , moment is maximum . However , in this question , i found that when the shear foce is 0 , the moment is also 0 . I'm wondering is the ststemnet true ?
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Homework Equations

The Attempt at a Solution

 
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chetzread said:

Homework Statement


in the book , i was told that when the shear force is 0 , moment is maximum . However , in this question , i found that when the shear foce is 0 , the moment is also 0 . I'm wondering is the ststemnet true ?
swF2bVW.jpg


Homework Equations

The Attempt at a Solution

Obviously, if the beam is a cantilever, the shear force and the bending moment can both be zero at the free end. You won't find the maximum moment there in any event.

I think what the author was trying to say was that since the derivative of the bending moment, dM/dx = V, the locations where the shear is zero are also possible locations where the bending moment has a relative maximum or minimum.
 
SteamKing said:
Obviously, if the beam is a cantilever, the shear force and the bending moment can both be zero at the free end. You won't find the maximum moment there in any event.

I think what the author was trying to say was that since the derivative of the bending moment, dM/dx = V, the locations where the shear is zero are also possible locations where the bending moment has a relative maximum or minimum.
so , for the above case , shear force = 0 , moment = 0(minimum) ?
 
chetzread said:
so , for the above case , shear force = 0 , moment = 0(minimum) ?
Obviously.
 
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