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Introduction
You can make a rocket steamboat that moves without any batteries or electricity. Your steamboat will run on steam and physics! To learn more about how this works, see the explanation and links below. 

Collect the materials and follow the instructions to make your very own rocket steamboat. 
      Safety Information
Experiments are dangerous, but scientists are always safe!

→Always have an adult help you collect the materials and conduct the experiment.
→This experiment uses many dangerous items, such as candles, hammer and nails, and hot water. Be very careful!

 

 

    
Materials
→ cork (that fits snugly in metal tube)  
→ metal tube (such as a cigar tube)  
→ two18 in. (46 cm) long pieces of hard wire (such as clothes hanger wire)  
→ two food warmer candles (in metal)  
→ balsa wood (4 in. x 8 in. x 1/2 in.)  
→ masking tape  
→ hammer  
→ nails  
→ matches  
→ pliers  
Instructions
 
1) Snugly fit the cork into the top of the metal tube. Then, poke a hole through the cork with a nail. If you don't poke a hole through the cork, your boat may blow up!  
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5)

 Wrap the wires tightly around the tube 1 inch from each end. Twist the wires tightly with the pliers so they don't slide around on the tube.

Cut a boat shape out of the balsa wood.  One end should be shaped like a triangle. (picture)

Hammer two large nails through the balsa wood, one at the front end and one at the back end of the boat.  (Do not hammer your paw by mistake) The nails should be about one inch from the front and back edges. The nails will help the boat balance, like rudders. (picture) 

Attach the two candles to the front and back ends of the boat using the masking tape.  The candles should be about 1 1/2 inches away from the front and back edges of the boat. (picture)  

  
 
 
 
6) Suspend the metal tube above the candles (cork end facing the back of the boat) by wrapping the wires around the base of the boat. Secure the wires in place on the boat's underside using the pliers.  

 

 

 

 

  
7) Take the cork out of the tube and fill the tube with very hot water.  Check that the hole in the cork is wide enough for water to escape.  
8) Fill up a bathtub or large sink with water. Taking your boat to the ocean is a bad idea. The Knowledge Bears have lost many boats this way.  
9) Place your boat on the water and have an adult light the candles. Wait . . .

Zoom!

 
Explanation
  When you put water in an ice cube tray and leave it in the freezer, the water turns to ice in the cold temperature.  Likewise, when you heat water to a high temperature, as you do this experiment, the water turns into steam. 
  The steam then escapes through the hole you made in the cork. When this happens, the force of the steam going backwards pushes the boat forward.  Why?  (picture)  

 

 

 

 

 
  Newton's Third Law of Motion says:
"For every action there is an equal and opposite reaction."
  Are you sitting down? If so, your body is pushing down on the chair. Did you know the chair is pushing you back? This "pushing" is called a force. Your body applies a downward force on the chair, and the chair applies an upward force on you. (picture)  

 

 

 

 
  Here's another example: imagine you are a fish with a fin on each side of your body. You push your fins backward, applying force to the water. The water pushes on your fins in the opposite direction, moving you forward. (picture)   

 

 

 

 
  When you push down on the chair, that is an action. When the chair pushes you up, that is a reaction. When the fish's fins push backwards on the water, that is an action. When the water pushes forward, that is a reaction. 
  Sir Isaac Newton figured out that actions and reactions are always equal. This means that an action and a reaction will have the same force. 
  He also said that the action and reaction are opposite. This means that if an action pushes in one direction, the reaction pushes in the opposite direction. You push the chair down, it pushes you up. The fish pushes water backward, the water pushes the fish forward. Wheels on a car spin backward against the road; the road pushes the wheels forward, and the whole car moves forward. 
  So let's take a look at how Newton's Third Law of Motion makes the rocket steamboat work.  When the steam is released from the tube, it applies a backward force on the rest of the air around the boat. The boat is then pushed forward with equal force. (picture)  

 

 

 

 
Links
A Century of Physics
Explore the history of physics, including Sir Isaac Newton and his laws of motion
The Physics Classroom
Learn more about Newton's three laws
BoatSafe Kids
Experiment with different boat designs
How Does Matter Change Forms?
A short explanation of how water changes to steam
Suzy's World: Steam
Some facts about steam and steam power
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