Question

Which among the following is the correct formula for lift?

(a) D = Cl * A * 0.5 * r * V^2

(b) D = Cl * A * 0.5 * r * V*2

(c) D = Cl * A * 0.5 * r * V/2

(d) D = 0.5 * r * V

This question was posed to me in quiz.

Asked question is from Types of Forces Acting in Moving Fluid topic in division Dimensional and Model Analysis of Fluid Mechanics

Answer 1

The correct choice is (a) D = Cl * A * 0.5 * r * V^2

To elaborate: The lift force is a force that acts in the perpendicular direction to that of the relative flow velocity. It acts in the perpendicular direction with respect to a surrounding fluid flow. Thus, the correct option is D = Cl * A * 0.5 * r * V^2.