What is the angle of attack of lift producing airfoil?

A)
Angle of attack is zero
B)
Angle of attack less than zero
C)
Angle of attack remains the same
D)
Angle of attack greater than zero

Correct Answer :   Angle of attack greater than zero


Explanation : A lift producing airfoil either has camber or is translating in a uniform fluid at an angle of attack greater than zero. Moreover, it must have a sharp trailing edge. An airfoil generates lift by exerting a downward force on the air as it flows past.