Question

If a body is in equilibrium under a set of non-collinear forces, then the minimum number of forces has to be

• A. Four
• B. Three
• C. Two
• D. Five

Answer 1

The correct option is B

Three

Explanation:

Option B: Three

Draw the required diagram for the non-collinear forces,

Non-collinear forces are those forces whose line of action does not lie on the same line.

1. The body must have at least three forces to be in equilibrium under a set of non-collinear forces.
2. Collinear force: Collinear forces are those that act along the same line for a system when their lines of action are aligned.
3. Non-collinear force: non-collinear forces are ones whose line of action does not follow the same line as the line on which the force is acting. Collinear forces follow the same line as the line on which the force is acting.
4. Three or more force points must be on the same line for a force to be considered collinear.
5. Collinear forces can be represented by ${\hat{F}}_b\ne {\hat{F}}_a$.

Hence, the correct option is B.