Hang Gliding
1. (answer: Gravity, Lift, Drag).
2. (answer: A--the force of lift must be greater than the force of gravity.)
3. (answer: How high the hang glider can go, how far it can travel and how long it can stay aloft.
4. (answer: Lift).
5. (Answer: Rising air, which can be created by heat (called thermal lift) or by air flowing up a
mountainside (called Ridge lift).)
6. (answer: The hang glider and rider colliding with air molecules).
7. (answer: C).
8. (answer: Birds soar on rising columns of air).
9. (answer: Hot air, or thermals).
10. (answer: Drag is increased, lift is decreased).
Surfing
1.
(answer: Wind)
2. (answer: Weather forecasters call these three factors "wind velocity," "fetch" and "duration,"
respectively)
3. (answer: a strong wind blowing over a large expanse, or long distance)
4. (answer: less)
5.
(answer: a large, energetic wave).
6.
(answer: gravity and buoyancy).
7. (answer: Equal and opposite; 0).
8. (answer: When the surfer moves the water exerts an equal and opposite force on the board).
9. (answer: The 3rd).
10. (answer: density, which is weight per unit volume)