Reduction of a simple distributed loading problem

[Renan]

Why can't we use the NOTE method (exercise 4.21) on the exercise 4-156 ?

A = ab/3 = (10.500)/3 = 1666,66 N --> this not right

 

[kuruman]

View attachment 226820
Why can't we use the NOTE method (exercise 4.21) on the exercise 4-156 ?

Because the location function is different. In one case is goes as $x^2$ and in the other as $x^3$. If you do the integral in each case, you will get a different answer.