Question

The moment applied at joint O for the unit rotation is
[All member have same length and same flexural rigidity]
______ $\frac{EI}{L}$

• A. 8

Answer 1

The correct option is A 8
$StiffnessofmemberOA=\frac{3EI}{L}$
$StiffnessofmemeberOB=\frac{4EI}{L}$
$StiffnessofmemberOC=\frac{EI}{L}$

$\therefore \Sigma k=\frac{4EI}{L}+\frac{3EI}{L}+\frac{EI}{L}$

$=\frac{8EI}{L}$

$\therefore \frac{M}{\theta }=\frac{8EI}{L}$

$\Rightarrow M=\frac{8EI}{L}\theta$

$\therefore For\theta =1unit$

$M=\frac{8EI}{L}$