Theorys of Flight

There are three theorys as to what generates lift. The first one is the Bernoulli Effect. The Bernoulli effect is where the wing is curved at the top and the air speeds up when it goes over the top and doesn't go as fast when it travles along the bottom creating low air presure on top and high air presure on the bottom creating lift (below).
The second theory is the Newtonian Theory. The Newtonian Theory is when the wing is given an angle of attack the wing basicly skips over the air keeping it's self in the air (below).
The third is the cerculation theory. This is that when the wing is given an angle of attack the air moves slower on the bottom still and the air creates high presure creating lift.