What is a free body force diagram in airoplanes and how it works?

Question

plzz explain

Answer 1

A free body diagram is a physics drawing that illustrates the forces on an object. In a [moving] airplane, assuming friction, you'd have:

Fg > the force of gravity pulling the plane downward

Fk > the force of kinetic friction, or "drag" on the plane

Fapp > the force, or pull of the engines in the direction of motion of the plane, generally forward.

If the plane was on a tarmac, for instance, you'd also have

Fn > the equal and opposite reactive force that the surface exerts on the plane to keep it from breaking through