Boat base (choose one of the following):
- Egg carton
- Cardboard
- Plastic container (i.e. tupperware)
- Aluminum foil
- Heavy paper
Mast (choose one of the following):
- Wooden skewer
- Chopsticks
- Popsicle sticks
- Craft sticks
- Small tree branches
Sail supplies (choose one of the following):
- Construction paper
- Cloth
- Foil
Glue or tape
Optional: Pennies or another small object to add weight to the boats.
Testing the Wind Materials
Large tray or bucket to hold water
Fan
Hairdryer
Optional: Straw (metal, silicone, or paper to limit the use of single use plastics)
Teacher Recommendations:
Boats can take all shapes and sizes - students can get creative with how they construct their boat—as long as it floats and catches wind!
When considering what to use to represent the ocean, keep in mind that the boats will be moving across the surface of the water. Using a container with a larger surface area will yeild the best results. If there is a pond nearby, consider using that!
Follow along on your worksheet to build a boat and test the winds!
Build a model of a sailboat:
Create a boat base from your chosen material (i.e. folded tinfoil, cardboard box, plastic container).
Cut a rectangle from construction paper to make your sail. Decorate it!
Poke two small holes in line at the top and bottom of the sail. Get help from your teacher as needed!
Image
Image caption
Fig. 3. An example of a model sail boat.
Image copyright and source
Image by Emily Sesno
Attach the sail to the mast (chopstick, skewer, stick, or similar material) by guiding the stick through the holes. Add tape or glue as necessary to secure it (Fig. 2).
Create an ‘ocean’ (bowl or pan of water) and place your sailboat on the surface of the water.
Optional: add pennies or other items to the boat to help weigh it down and sit properly in the water.
Draw a picture of what your boat looks like. Label the parts.
Test the winds:
Before testing the effect of wind on your sailboat, think about your hypotheses and record them on your data table:
How will the force of wind affect the motion of my sailboat? (i.e. Will there be a difference in your boat's movement when the wind is weaker compared to when the wind is stronger?)
How will the direction of wind affect the motion of my sailboat? (i.e. Will your boat move sideways, straight ahead, backwards, etc.?)
Conduct your trials.
Trial #1: Direct Winds
Blow gently on your sailboat using your breath. You may also blow through straw to help direct your ʻwind.ʻ (Please use a metal, cardboard, or other type of non-plastic straw!)
Record your observations on the data table.
Trial #2: Indirect Winds
Use a fan to blow wind toward your sailboat. Place the fan pointing in the general direction of the sailboat. Turn the fan onto the lowest setting.
Record your observations on the data table
Trial #3: Strong Winds
Use a hairdryer to blow from different directions on your sailboat.
Switch between high and low settings.
Record your observations on the data table.
Trial #4: Equal Winds
Using either hairdryers or your breath, blow on one side of your sailboat while your partner blows with the same force on the opposite side.
Record your observations on the data table.
Data Table:
TEST: What will I do?
PREDICTION: What will happen?
OBSERVATION DATA:
What do I observe? (use words and/or a labeled drawing.)
Trial #1 - Blow directly on the sailboat
Trial #2 - Blow indirectly toward the sailboat
Trial #3 - Blow strongly on the sailboat
Trial #4 - Blow at the same time as your partner (facing each other) on the sailboat
Activity Questions:
When a sailboat is floating but not moving, the forces acting on it are (circle one):
balanced
unbalanced
When a sailboat is moving, the forces acting on it are (circle one):
balanced
unbalanced
When your boat is not moving, there are forces acting on it to keep it floating on the water. However the boat does not move because those forces are balanced.
What balanced forces are acting on the floating sailboat?
What additional forces could you apply to cause the boat to move?
What happened when you blew gently on the sailboat?
What happened when you blew harder?
What changed when your partner blew at the same time as you? Were the forces balanced or unbalanced?
When you push a ball and it rolls on the floor, is this a balanced or unbalanced force?
You have been testing wind as an unbalanced force that moves sailboats. Give an example of another unbalanced force that can cause an object to move.
How might sailors use the knowledge of winds to plan for voyages?
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Exploring Our Fluid Earth, a product of the Curriculum Research & Development Group (CRDG), College of Education. University of Hawai?i, 2011. This document may be freely reproduced and distributed for non-profit educational purposes.