Extreme Science: Penny Shine

What you will need:

  1. Jumbo craft sticks
  2. ¼” dowel (cut to 6” length)
  3. ¼” wood dowel cap
  4. Glue (Hot glue is the quickest but wood glue would also work)
  5. Bowl
  6. Water
  7. Drill
  8. ¼” drill bit
  9. Adult supervision

Procedure:

1. Carefully drill a ¼” hole in the center of a large craft stick. These will split easily so take it slow and easy.

2. Place the jumbo craft stick in a bowl of water for about 20 minutes.

3. Remove the craft stick from the water and hold each end firmly while slowly and carefully twisting the craft stick to shape it like a propeller. This process may take about five minutes to slowly shape your stick so that it will remain “twisted” once you let it dry.

4. Once the stick(s) have dried, place one 6” long dowel through the hole in the center.

5. Place a wood dowel end cap on the table (hole side up) and carefully place some hot glue in the center of the hole.

6. Insert the top end of the dowel into the end cap. This should force some glue out around the end of the dowel and around the base of the end cap. Quickly slide this down against your propeller to attach the end cap and dowel to your propeller as shown.

7. With your hands flat and your palms together, place the helicopter with the propeller towards the top between your palms. Quickly slide one hand forward (away from you) and the other hand in the opposite direction to cause the propeller to spin in the direction of the edge that is pointing UP . Release the helicopter at the end of this movement allowing the helicopter to take off!

What is going on?

There are four basic forces to flight: thrust, drag, gravity and lift. By soaking the craft sticks in water, then twisting them, you created a propeller! A propeller will create lift when spun in the correct direction due to the shape. The leading edge (the edge that is pointing up) is cutting through the air and the trailing edge is lower which then pushes the air molecules down. This action will create lift. When you spin it fast enough, the lift that is created will overcome the force of the gravity that is pulling down on your helicopter and it will actually take off up into the air. The height that your helicopter flies will depend on the angle of the propeller blades and how fast you can spin it. Once it leaves your hand, it will take off but will eventually loose energy and slow down causing it to come back down to earth.

Radical Rick

Extreme Science

www.ExtremeScienceFun.com

509-892-7621