Why do airplanes stay in the air?
There is no net force on them
They have wings
They have an engine

What four forces must be balanced?
Thrust, lift, gravity, pull
Pull, lift, gravity, push
Thrust, lift, gravity, drag

What is a crucial part of flying?
The engine on the plane
Getting air molucules to push the plane up
The wings

What part of the wings crash into air molecules more violently?
The undersides
The uppersides
All parts of the wings

Low pressure on the top of the plane plus high pressure on the bottom means:
The plane has lift
The plane glides
The plane drops

What direction do engines push air?
Forwards and backwards

For the most efficient engine it is good to have:
A really big propeller and a really small jet
A really big jet and a really small propeller
A really big jet and propeller