In this lesson, you'll introduce your students to the four forces of flight--drag, lift, thrust, and weight--through a variety of fun-filled flight experiments. Students will "fly" for short periods and then evaluate factors that might either increase or decrease their "flight" duration.
You might begin the activity by asking your students the following questions:
- Can you fly? How high do you think you can fly? How long do you think a very good jumper (e.g., Michael Jordan) can stay in the air?
- Have your students complete the "How High Can You Fly?" (Activity 1A) and "How Long Can You Fly?" (Activity 1B) exercises in Activity Set 1. Ask them to examine the duration and height of their flights. Are they surprised at the results?
- Refer to the "Think About It" (Activity 1C) exercise in Activity Set 1. Ask your students to observe each of the cartoon figures. What are they doing? How might the cartoon figures' actions and environments allow them to jump higher and for longer periods than anyone in class? What else could students do to make their jumps last longer?
Possible observations of the cartoon figures
Parachute figure--This figure can stay airborne longer because the parachute slows the person's fall. Demonstrates drag.
Helmeted figure--This figure can jump higher because the sleek helmet decreases air resistance. Demonstrates drag.
Figure with springy shoesThis figure can jump higher because the springy shoes provide a power boost. Demonstrates thrust.
Moon-walking figure--This figure can jump higher on the Moon than on Earth. The smaller gravity on the Moon means that the figure weighs less theere. Demonstrates the force of weight.
Figure with propeller hat--The spinning propeller creates a difference in air pressure, which pushes the figure upward. Demonstrates lift.
Some other possible actions to make jumps last longer
Thrust--Jump off a trampoline or diving board; launch yourself with a pole vault, catapult, or rocket; or exercise to get stronger mmuscles.
Weight--Wear lighter clothing, lose weight, or travel to a planet with smallergravity than Earth's.
Drag--Wear skin-tight clothing.
Students may suggest other methods to make their jumps last longer. You may wish to organize their thoughts by drawing a simple chart on the chalkboard (see below).
Drag--The resistance caused by the shape of an object and its movement through the air.
Lift--The upward force created by a difference in air pressure. Moving air creates this difference as it moves around an airfoil ((e.g., a wing).
Thrust--The force developed by a propeller or jet engine that drives an airplane through the air. (In the jumping activity, studentss' leg muscles provided thrust.)
Weight--A measure of the heaviness of an object.