# Fixed end moment

1. Apr 20, 2017

### fonseh

1. The problem statement, all variables and given/known data

In the book (photo 1 ) , it's stated at the left span, the fixed end moment is clockwise , while on the right span , the fixed end moment is anticlockwise . But , accroding to wiki (photo2) , it's stated that at the left span of the beam , the fixed end moment is anticlockwise , while on the right span , it's clockwise ...

In both cases , clockwise moment is assigned as positive . Which case is correct ? I'm confused . ht//en.wikipedia.org/wiki/Fixed_end_moment

2. Relevant equations

3. The attempt at a solution

IMO , only one of it an be correct . This is because as the In both cases , clockwise moment is assigned as positive . When we drawing the bending moment diagram , it will lead to different answer .

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2. Apr 20, 2017

### scottdave

It looks like the book is talking about the equivalent moment of the beam loading (note the circular arrow is on the beam side). The Wikipedia article appears to be referring to the wall's reaction moment to the beam loading. Note that you should expect these two moments to be equal magnitude and opposite direction, since the beam has not been caused to spin.
Similarly, when you are standing on the ground, often we talk about your weight as a force pushing down on the ground. But there is also the equal force of the ground pushing up on you, keeping you from falling into the ground.

3. Apr 20, 2017

### fonseh

So , fixed end moment is the reaction moment ?

4. Apr 21, 2017

### scottdave

That is what it looks to me, in the Wikipedia article is referring to, the way they drew the arrows.