---

Beginner's Guide to Aerodynamics is a "textbook" of information prepared at NASA Glenn Research Center to help you better understand aerodynamics. Click Beginner's Guide Index to access the list of slides. Open the slides called What Is Lift?, Incorrect Theory #1, Incorrect Theory #2, and Incorrect Theory #3 (with text) and read the explanations on lift and the popular incorrect theories on how lift is produced. Then using the information found in these slides, complete the questions below designed to demonstrate your understanding of the theories.

1. Compare and contrast the incorrect lift theories #1 and #3.

    

2. Contrast the incorrect lift theories #2 and #3.

    

3. Which theory(ies) cannot explain why airplanes can fly upside down?

    

4. Which theory(ies) cannot explain why the upper surface of a wing has an effect on lift?

    

5. Which theory(ies) cannot explain why the air flowing past the lower surface of a wing has an effect on lift?

    

6. Explain the correct theory of lift in your own words.