Bending moment for curve and straight beam

[Sadeq]

It’s clear that bending moment for a curve beam is less than straight one
And you can attribute this to moment of inertia, but there is something i don’t understand
Which is if i have straight beam with small moment of inertia or huge moment of inertia simple supported beam), the moment will not differ, so why it will differ in curve beam.

 

[Sadeq]

UP

some help please

 

[LawrenceC]

Are you confusing bending stress with bending moment? Bending moment is a function of load and distance and has nothing to do with moment of inertia. Bending stress is dependent on the moment of inertia.