What is the force at the joint C on the right beam?

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The discussion revolves around calculating the force at joint C on a beam system with a fixed support at A and a free-moving support at B. The left beam is 2m with a 6[kN] load, while the right beam is 3m with a 10[kN] load. An upward force of 5[kN] is needed at joint C for equilibrium, leading to the equation 1.4F = 16, resulting in F being approximately 11.43. However, there is a suggestion that the correct force should be F=10, assuming joint C is pinned. A recommendation is made to adjust the distance in the moment calculation to align with textbook answers.
Karol
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Homework Statement


Pay attention that the left support A is a fixed axis and the right, B, is a free moving axis. C is a joint.
The left beam (to the joint): 2m, 6[kN], the right beam: 3m, 10[kN]. What is the force F.

Homework Equations


Moments: ##M=F\cdot L##

The Attempt at a Solution


To support he right beam 5[kN] must be applied upwards on the joint. moments around A:
$$1.4\cdot F=6\cdot 1+5\cdot 2$$
$$1.4\cdot F=16\rightarrow F=11.43$$
It should be F=10
 

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I assume C is a pinned joint?

It seems to me that there is a mechanism where joint C would need to move up in order to develop a sufficient load from the right side beam for equilibrium.

You may want clarify things and draw a free body diagram with all the reaction forces and beam lengths labeled.
 
@Karol I get your answer.

I think you'll find that if you change that 1.4m to 1.6m your answers will all be in agreement with the book. :wink:
 
Thanks
 
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