If a force (F) is acting on a rigid body at any point P, then thi
If a force (F) is acting on a rigid body at any point P, then this force (F) can be replaced by:
A. An equal, opposite and parallel force (F) applied at point Q together with a couple
B. An equal, opposite and parallel force (F) only at point Q
C. A moment at point Q only
D. An equal, parallel and same sense force (F) at point Q together with a couple
Please scroll down to see the correct answer and solution guide.
Right Answer is: D
SOLUTION
Concept:
Two force systems are equivalent to each other if they have the same resultant force and the same resultant moment.
\({\rm{\Sigma }}{F_{system - 1}} = {\rm{\Sigma }}{F_{system - 2}}\)
\({\rm{\Sigma }}{M_{system - 1}} = {\rm{\Sigma }}{M_{system - 2}}\)
If a force is replaced off its line of action, then a couple is added to the force system so that the newly replaced system has the same moment as the original system.
Note:
If a force is moved along its line of action then the new system is equivalent to the original system.