Summation of forces equals zero is also known as what condition?

• A. Equilibrium
• B. Balance
• C. Steady state
• D. Stability

Answer: (A)

When the sum of all forces acting on a body is zero, there is no net force, so there is no translational acceleration. If the body is at rest, it stays at rest; if it’s moving, it continues with constant velocity in a straight line. This state is called equilibrium, specifically translational equilibrium when we’re talking about motion and forces in the plane of motion.

The other terms don’t fit as precisely. Balance is a general everyday word, not a formal physics condition. Steady state describes a system with no net change over time in a broader sense, often involving ongoing processes. Stability refers to how a system responds to disturbances, not the instantaneous balance of forces.