The Power of Steam

May 28, 2009

by: Tami O’Connor

Although Robert Fulton is usually remembered as the inventor of the steamboat, it was actually John Fitch who built the first successful steamboat in 1787. Unfortunately, John Fitch ran into financial difficulties which opened the door for Robert Fulton to design and test the Clermont, which was the first commercially successful steamboat, in 1807. Since that time, there have been many improvements on the initial design, but the science behind the steamboat engine is fascinating.

Educational Innovations carries Putt-Putt Steam Boats that are wonderful reproduction toys, which can be used to teach many scientific principles. The science behind how they work is rather complex and often disputed. We would be delighted to hear input from our teachers.

How Do They Work?

One theory is that a heat source (small candle, or cooking oil and wick) heats the water in the boiling chamber creating a brief burst of steam that is expelled through the pipes in the rear of the boat. The force of the expanding gas (steam) pushes the boat forward. Since there is a limited amount of water in the chamber to start with, the exit of the gas creates an area of lower pressure in the boiling chamber. This allows the atmospheric pressure that is pressing down on the water to force more water into the chamber, allowing it in turn to be heated to boiling, and repeating the process again and again until the fuel is exhausted.

Suggested Activities Note: Use caution! The boat will get hot.

Run your Putt-Putt boat in a small pool or washtub.

• Have students predict how many times around washtub the boat will travel using just one candle or the amount of time each trip will take.
• Have your students calculate the average speed of the boat by measuring the distance around the test chamber, and timing each revolution.
• Have students determine if the speed of the boat changes as the fuel is consumed? Does it move more quickly at the beginning, middle or end of the life of the candle? Other variables could include adding additional weight to your steamboat or changing the temperature of the water you boat travels through. Ask students to brainstorm additional variables, which could potentially affect the speed of the boat through the liquid.
• Use alternate fuels in your boat. Cooking oil and a scrap of cotton fabric works well. As do small wood shavings. Does the type of fuel affect the speed at which the boat travels? Do some fuels make the boat go further? Go faster? Both? Neither? Make a graph of fuel type, vs. speed and distance.
• For younger students, simply use two different boats to compare variables. Have the boats race each other changing only one variable at a time.

There are a number of websites that give instructions on how to build your own steamboat. This is an excellent idea for a science fair project!

A Note on Conservation

Perhaps we should have called this section “A note on CANservation”. Take a close look at our boats – you will discover that they are made from metal stamped out of a wide variety of cans and containers (some will be misprinted paint cans, others holiday gift tins, still others can be very hard to figure out). This is a wonderful example of how materials that might have had to be re-melted or even end up in landfills can be used to make products that are fun and interesting.

On Your Hands

May 8, 2009

by: John Fedors

As infants become aware of their surroundings, fingers, toes, toys, pacifiers and other objects that can be handled, always end up in their mouths. It’s no wonder that parents become first fascinated, then concerned, and eventually oblivious for it seems almost everything ends up being “tasted”.

Alertness, curiosity, and fascination inspire investigation , which begins at an early age. Teachers encourage this direction and take advantage of it. Repetition of this experience should be reinforced and developed to become habitual. Children come to recognize, “It Makes Sense” .

Did you wash your hands? How many times have we heard this? How many times do we “forget”? This simple, though important task, must be difficult to instill, for so many fail to perform it.

We are continually reminded during our early lives and even as adults, that hand-washing must be difficult or of low priority, because we so often forget. It would seem that demonstrating the effectiveness of using soap and water should be encouraged!

The use of Glo-Germ powder may help to develop this habit. When I mention this to teachers, most are aware of its uses, but many are not. Some teachers are aware because the school nurse or health teacher has demonstrated it in their class, then it is forgotten. Teachers have multiple opportunities to demonstrate and reinforce this awareness.“

Glo-Germ” is a nontoxic product, which simulates a microorganism. This product is not easily visible but fluoresces when exposed to UV light. It is used in hospitals, fast food chains, and schools to demonstrate the effectiveness of hand washing.

Suggested Uses or Demonstrations:

1. Either: sprinkle Glo-Germ Powder on a giant microbe, (Salmonella, Common Cold, Flu).
• Leave the microbe on the desk with a Do NOT Touch sign (of course if your students are anything like mine, they will most certainly touch…).
• Pass the germ around the room carefully. DO NOT let students TOSS the microbe as the powder, similar in texture to flour, could irritate lungs.
• Sprinkle some powder on every 3rd or 4th handout distributed in class and wait 10-15 minutes.
• Place some powder on your hand and shake hands with a student who then passes the “germ” on to another student and then another…

Then go around with a UV light (I recommend using a portable hand held long wave light) illuminate the powder residue, and demonstrate microbe transmission.

1. Glo-Germ lotion is used to demonstrate hand washing technique. Shake the lotion and have the students rub it into their hands on Friday afternoon. Check their hands first thing Monday morning. See differences between boys and girls. Use your UV light to demonstrate effects of hand washing.
2. The lotion or powder can also be used in forensics activities by putting lotion on: door knobs, draw pulls, texts, fire alarms, manuals, facet handles, equipment, or handouts