What is an equilibrant?

Hint: As we know that, equilibrant is nothing but it’s a type of force that brings everything back into balance. A force in a physics experiment is an example of an equilibrium. A force equal to the cumulative sum of vector forces, but opposite to it; the force that balances other forces, bringing an item to equilibrium.

Complete answer:
A force that brings a body into mechanical balance is known as an equilibrant force. A body has zero acceleration when the vector sum of all forces acting on it is zero, according to Newton's second law. As a result, an equilibrant force has the same magnitude as the sum of all other forces operating on a body but the opposite direction.
Assume that two known forces are pushing an object and that an unknown equilibrant force is working to keep it in place. One force points to the west and has a magnitude of $10N$ , and the other points to the south and has a magnitude of $8N$ . The resultant of these two forces has a magnitude of around $12.8N$ , which is also the magnitude of the equilibrant force, according to the Pythagorean theorem. Trigonometry determines the angle of the equilibrant force to be roughly 51 degrees north of east.
Each force is the equilibrant of the other if two forces are equal in opposite directions. The equilibrant force is the solitary force that generates equilibrium when applied at the same spot (of equal magnitude and opposite direction).

Note:
Equilibrium is the state of a system in which conflicting influences are balanced, resulting in no net change, whereas equilibrant is a force equal to, but opposite to, the resultant sum of vector forces; it is this force that balances other forces, bringing an item to equilibrium.