The resultant force is the vector sum of all the forces acting on an object. It determines the net effect of all the forces and the resulting acceleration or change in motion. If the resultant force is zero, the object will remain at rest or continue moving with constant velocity.

Equilibrant Force:

The equilibrant force is a force that balances or cancels out the net effect of all the other forces acting on an object. It is equal in magnitude but opposite in direction to the resultant force. When the equilibrant force is applied, the object will be in equilibrium, meaning it will not experience any acceleration or change in motion.

Comparison:

In simpler terms, the resultant force represents the overall effect of all the forces on an object, while the equilibrant force is the specific force that counteracts the resultant force to achieve equilibrium. When the resultant force is non-zero, the object will accelerate or change its velocity. However, when the resultant force is zero (due to the presence of an equilibrant force), the object will remain in equilibrium without acceleration.

To summarize:

- Resultant force: The vector sum of all forces acting on an object, determining its net effect and acceleration.

- Equilibrant force: The specific force that opposes the resultant force to achieve equilibrium, resulting in no acceleration or change in motion.

- Comparison: The resultant force represents the overall effect of all forces, while the equilibrant force ensures equilibrium by canceling out the net effect.