Question Detail
Question
A body is said to be in equilibrium when
Correct Answer
Option B is the correct answer.
Detailed Explanation
A body is in equilibrium when the net force (resultant force) acting on it is zero. This condition ensures no linear acceleration (translational equilibrium). While a body at rest (static equilibrium) satisfies this, a body moving with constant velocity also has zero net force and is in dynamic equilibrium. Option A is too restrictive, and option C is a special case of equilibrium.
Hint
Equilibrium is about forces balancing, not necessarily being at rest.