Why do I have a bending moment and an axial displacement here?

[Mech_LS24]

Homework Statement

I have a flexure where a asymmetrically force is applied. Why do I have a bending moment + a axial force displacement instead of a bending force?

Relevant Equations

F*l^3/3*E*I
(F*L)/E*A

Hello,

I have an flexure where the force is applied asymmetrical, I just can't visualize why their should be a bending moment instead of an bending force? How can I distinguish those? Thanks!

 

[hutchphd]

Homework Statement:: I have a flexure where a asymmetrically force is applied. Why do I have a bending moment + a axial force displacement instead of a bending force?
Relevant Equations:: (M*L)/EI
(F*L)/E*A

I just can't visualize why their should be a bending moment instead of an bending force?

Your question is not well defined, for me at least. The moment of any vector is its value acting through a perpendidicular distance (the cross product to be technical).
Your relevant equation are not equations. Perhaps that would be a place to start.

 

[Mech_LS24]

Sorry for that.

They ask what the deflection is at Point A. I thought their should be axial deflection and a bending force deflection (1 and 2). But the book states that the should be a bending moment instead of a bending force. I have added the equations in the sketch, and here below:
Delta1 = F*L/E*A
Delta2 = F*l^3/3*E*I

*I see the one equation in the original post is wrong, I will try to fix that.

 

[haruspex]

I don’t understand the distinction between bending moment and bending force. A force can result in bending because it has a moment about the centre of the rigid attachment.

 

[Lnewqban]

Could you post the original text and diagram?

 

[Mech_LS24]

Could you post the original text and diagram?

I am afraid not, it's from a document which isn't allowed to be shared.

The only thing here, I can't distinguish bending moment and bending force..

 

[Lnewqban]

I am afraid not, it's from a document which isn't allowed to be shared.

The only thing here, I can't distinguish bending moment and bending force..

As explained by @haruspex above, there is no moment without a distance and a force.
In this case, the distance of interest seems to be the one separating the neutral fibers from the point of application of the axial force.