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
What part of the wings crash into air molecules more violently?
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