Question

While an airplane is in flight, four forces act on it. Thrust is caused by the airplane's propellers pushing through the surrounding air, pulling the airplane forward. Drag is caused by the air smacking into the plane's surface, pushing it backward. Lift is caused by the air rushing over the wings, pushing it upward. And weight is caused by gravity pulling the plane downward. Which force acts on the plane at a distance?

Answer 1

The answer would be weight

Answer 2

Among these 4 forces, the only force acting on the plane at a distance is weight.

In fact, weight is due to gravity, which is a non-contact force (it acts also from a distance). All the other forces, instead, are due to the contact between the plane (or parts of it) with the surrounding air: without the air, all the other 3 forces (thrust, lift, drag) would not be present, while weight would be always present.