2. Paper Helicopters Science Design Options Flight Suggestions

3. Science What makes it fall? What makes it slow down as it falls? Does it continue to speed up as it falls? Which way does it spin? Always?

4. The downward force is: Gravity

6. The Apple and the Moon Newton didn’t discover gravity Galileo – concept of inertia. The moon follows a curved path because of gravity. Gravity extends throughout the universe

7. Your helicopter will fall at a constant speed when it reaches: Terminal Velocity This happens when gravity force = friction force. Skydivers reach this point at about 125 mph Parachutist reach it at about 10-15 mph

8. What slows your helicopter down? Fluid Friction Air is a fluid? Sure. Fluids flow; both gas and liquid Also called: Air resistance – friction that acts on something moving through the air More friction = more resistance

9. Design Options Same design but larger or smaller Change wing size and/or shape Change body size and/or shape Other ideas?

10. Sketch several ideas….. This one shows how to design wings that tilt inward What if you tried outward? Experiment!

11. Tips for a good flight…. Angle your wings slightly upward Make sure the wings are equal in size and shape Try releasing it in a variety of ways The sooner it starts spinning the better

12. Have Fun!!