Question

In the equation, \(\int_{L} \sigma^T  \epsilon(\phi)Adx -\int_{L} \phi^T f Adx -\int_{L}\phi^Tdx – \sum_{i}\phi_i P_i=0\) First term represents _______

(a) External virtual work

(b) Virtual work

(c) Internal virtual work

(d) Total virtual work

I had been asked this question during an interview.

Origin of the question is One Dimensional Problems in chapter One Dimensional Problems of Finite Element Method

Answer 1

Correct option is (c) Internal virtual work

Explanation: In the given equation first term represents internal virtual work. Virtual work means the work done by the virtual displacements. The principle of virtual work is equivalent to the conditions for static equilibrium of a rigid body expressed in terms of total forces and torques. The virtual work done by internal forces is called internal virtual work.