Question

Statement [A]: If a body is in equilibrium, then the resultant of the forces acting on the body is zero. Statement [B]: Action and reaction cancel each other as they act on the same body. Statement [C]: Centrifugal force is a pseudo force.

• A. A, B, C are all true
• B. A and B are true but C is false
• C. A and C are true but B is false
• D. B and C are true but A is false

Hint:

Action-reaction forces never cancel each other because they act on different bodies, not on the same object.

Answer 1

The Correct Option is C

This question checks three separate ideas at once: the condition for equilibrium, Newton's third law, and what a pseudo force is. It is easiest to test each statement against the definition it is built on, then match that to the four combined options.

Statement A says a body in equilibrium has zero resultant force. This is Newton's first law: no acceleration means no net force, so $\sum \vec{F} = 0$. Statement A is true.

Statement B says action and reaction cancel because they act on the same body. Newton's third law says action and reaction pairs are equal and opposite, but they always act on two different bodies, one on each object in the interaction. Because they never act on the same body, they never cancel each other's effect on one object. Statement B is false.

Statement C says centrifugal force is a pseudo force. A pseudo force only shows up because we are working in a rotating, non-inertial frame, it is not caused by a real push or pull between two bodies. Centrifugal force fits this definition exactly, so Statement C is true.

1. A, B, C are all true: wrong, because B is false, as shown above.
2. A and B are true but C is false: wrong on two counts, B is false and C is actually true.
3. A and C are true but B is false: matches the analysis exactly, A is true, C is true, B is false.
4. B and C are true but A is false: wrong, since A is true and B is false.

Let's summarize:

• Equilibrium always means zero net force on the body, so A holds.
• Action-reaction pairs act on two different objects and can never cancel on a single body, so B fails.
• Centrifugal force is a standard example of a pseudo force that exists only in a rotating frame, so C holds.

So the correct choice is option (3), A and C are true but B is false.