The force that opposes the effort force is called the resistance force. It acts in the opposite direction to the effort force and may come from factors like friction or gravity.
Gravity is the main resistance force on any aircraft. Wind resistance would be second.
The ratio of resistance force to effort force is a mechanical advantage.
Air resistance.
Air resistance is sometimes called drag. It is the force that opposes the motion of an object moving through the air.
The force applied to a lever is called the effort force. This force is used to overcome resistance at the load end of the lever in order to perform work.
Possibly water resistance (drag)
Terminal velocity.
It is friction. In air, it can also be called air resistance. Similarly, in water, it can also be called water resistance.
The force to be overcome by a simple machine is called the input force or effort force. This is the force applied to the machine in order to make it work against the resistance force or load.
The distance from the fulcrum to the resistance force in a lever is called the load arm or effort arm. This measurement helps determine the mechanical advantage of the lever system and how much force is needed to balance or move a load.
Inertia