If a coin is placed on the table then there will be two forces acting on it
1. Force on the coin due to table which is known as Normal reaction force and its direction will be vertical upwards
2. Weight of an object which is due to gravitational attraction force due to earth on the object
So here we can say that if the coin is at rest then the two forces will always be balanced and the two forces will equal in magnitude and opposite in direction.
Since the two forces are balanced here so coin is at rest and remains in equilibrium.
So FBD will contain two forces only which are equal in magnitude but opposite in the direction.
