An object at rest cannot remain at rest unless the net force acting on it is zero.

Quick Scoop Explanation

By Newton’s first law of motion (the law of inertia), an object at rest stays at rest as long as all the forces on it cancel out so that there is no overall (net) force.

That does not mean there are no forces at all; it just means they balance perfectly—for example, gravity pulling down and a table pushing up with equal strength, giving a net force of zero.

So among typical choices like:

  • Net force is zero
  • Net force is constant and nonzero
  • No forces act on it
  • Only one force acts on it

the correct condition is that the net force is zero.

In short: for an object at rest to stay that way, all forces must add up to zero so there’s no reason for it to start moving.

Information gathered from public forums or data available on the internet and portrayed here.