Question

Considering element connectivity, for example  for element ψ=[ψ1, ψ2]^n for element n, then the variational form is ______________

(a) ψ^T(KQ–F)=0

(b) ψ(KQ-F)=0

(c) ψ(KQ)=F

(d) ψ(F)=0

This question was posed to me in a job interview.

My question is taken from One Dimensional Problems topic in chapter One Dimensional Problems of Finite Element Method

Answer 1

The correct choice is (a) ψ^T(KQ–F)=0

Easy explanation: Element connectivity means Assemble the element equations. To find the global equation system for the whole solution region we must assemble all the element equations. For formulation of a variational form for a system of differential equations. First method treats each equation independently as a scalar equation, while the other method views the total system as a vector equation with a vector function as a unknown.