Question

Which of the following forces are considered in the equations of virtual work?

• A. External forces
• B. Internal forces
• C. Reaction forces
• D. Tensions in strings

Hint:

In the principle of virtual work, only external forces are considered. Internal forces and reactions are excluded unless explicitly stated.

Answer 1

The Correct Option is A

Step 1: Understand the principle of virtual work.
The principle of virtual work states that the work done by external forces during a virtual displacement is zero in equilibrium. Step 2: Internal forces do not contribute.
Internal forces do not appear in the virtual work equation because they cancel out in rigid body motion or equilibrium.