Part 2 – 15 minutes
Explain Newton’s first law that an object remains at rest until acted upon by an outside force or remains in motion till acted upon. We are going to place a sail on the boat. We will then place the boat in a pool with a fan exerting a force on it. The student will measure how far this force moves the boat.
Show the first part of this video discussing Newton’s first law.
http://www.physics4kids.com/files/motion_laws.html
  1. Explain the students will need to create an unbalanced force with the fan in order to push against their sails and move their boats.
  2. Hand out the clay, toothpick, straw, tape, index card, scissors and colored pencils.
  3. Design a sail on the index card, foam sheet or wax paper.
  4. Cut it out and color.
  5. Use a small blob of clay to hold the mast of the boat.
  6. Tape the straw or toothpick to the index card to act as a mast.
  7. Stick one end of the straw or toothpick into the clay. Tape the clay down if necessary.
  8. Get the stopwatch ready and place the boat in front of the fan, in the water.
  9. Time three seconds and measure how far the boat went.
  10. Calculate the surface area of the sail.
  11. Record on the board the surface area of the sail and how far the boat went.