Monthly Archives - February 2012

Energy is Energy is Energy…

Think back to when you were a little kid playing one of your most enjoyable family games on Saturday night. It involved rolling a die and moving around a game board, all while building a complex “mousetrap”, hoping that you wouldn’t get caught in its devious shenanigans or secretly wishing that its numerous “Energy Transfers” would fail to work!

Rube Goldberg was one of the pioneers of the energy conversion “machine”, albeit his ideas were a bit eccentric and downright kooky. Yet the public was fascinated by the possibilities of creating a machine that would actually perform a useful function by flipping a lever or pulling a string, thereby triggering a string of mechanical energy transformations that were compelling to watch at the very least.

In fact, the Honda Corporation used the idea of Energy transfer and conversion to promote their product to a new level; the actual parts of a Honda vehicle set up in a series of Rube Goldberg-like energy processes that ultimately showcased their newest model car. The video is real. It took 606 takes for it to work perfectly. For the first 605 tries some little thing didn’t work or move the way it was supposed to.

If you are wondering how the tires in the ad are rolling up the slope at 20 degrees, they’re weighted, with the weight positioned in the tire to be balanced at rest but when knocked, the weights naturally “fall” downward, therefore forcing the wheel forward. As the law of Conservation of Energy states, energy is lost with each knock as you can see when the last tire just barely makes it to the next link in the chain.

Arbor Energy Demonstration tools

The Drinking Bird is a science toy which repeatedly dips its beak into a glass of water. This is not perpetual motion, but a type of heat engine, exploiting the difference in temperature between the air and the water it dips into. Methylene Chloride makes a Drinking (Dipping) Bird work because it evaporates very easily (boiling point at approximately 100°F). Interestingly, Methylene Chloride is an industrial paint stripper and used widely in food processes to decaffeinate coffee! Giant versions of these toys have been proposed by scientists in desert climates, potentially used to generate tiny amounts of electricity. In principle, huge Drinking Birds could be constructed, but unfortunately at a prohibitively high cost per kilowatt at the present time.  Even though they are impractical, giant Dipping Bird Farms sure would be a sight to behold!

Drinking Bird

In Stock SKU: P3-5001
Energy Conversion Car Kit Meanwhile back in reality and your classroom, demonstrate to your students some of the easier ways to convert different forms of energy into powering a car or other science toys. Using this simple, but cost-effective kit will allow students to investigate the Law of Conservation of Energy! The Law of Conservation of Energy holds that energy cannot be created or destroyed but only converted from one form to another. This kit allows students to investigate this important conversion principle. Students can use the hand power generator to convert kinetic mechanical energy to electrical and use electrical energy to convert into sound, light, and motion using the interchangeable modules.

Energy Conversion Car Kit - "This Product Has Been Discontinued"

In Stock SKU: P3-4000
The Alternative Energy Conversion Kit allows students to investigate energy conversions. Improving the use of these forms and resources will reduce fuel costs, reduce the use of non-renewable energy sources and reduce harm to the environment. Students can question which generator of electricity works best in multiple situations.

Alternative Energy Conversion Kit

In Stock SKU: P6-2080
Reversible Thermoelectric Demonstrator brings the 2nd Law of Thermodynamics to life using it as a refrigerator or a heat engine. Immerse the two aluminum legs in baths of different temperatures, and produce electrical energy that turns the turbine! Unplug the banana jacks and measure the voltage output with a multimeter.  Connect a battery or DC power source to the two jacks. One leg will heat up while the other cools down. Measure the efficiency of this device and compare it to the Carnot Efficiency. Show energy conversions in action

Reversible Thermoelectric Demonstrator

In Stock SKU: P6-2700
A great source for Energy-Related Science and Technology Links for you or your students can be found at: 

Momentum – Tailgated by a Dart

In this lab, students will learn to estimate the speed of an object by applying conservation of momentum to an inelastic collision. Energy is not lost its transferred from one object to another. Students will fire a dart into the back of the free rolling car and measure the distance of the car, calculate the speed of the dart and car, and measure the mass of the car and dart.

Download Teacher Notes and Student Worksheets.

Required Equipment

Tailgated by a Dart Kit, stopwatch, meterstick, balance

Tailgated by a Dart Kit

SKU: PX-9501

Meter Stick 6 pack

In Stock SKU: P1-7072

Economy Digital Balance

In Stock SKU: 02-7000

Get Positive with your Charge!

I have found that over the years, creating a Positive charge in class using the conventional Glass rod/Silk combination just doesn’t produce a great enough charge to be able to demonstrate Conduction or Induction on pith balls, electroscope and other objects. The BEST way to produce a Positive charge is using the “Fun Fly Stick”! I used the Fun Fly Stick today in class and it creates plenty of Positive charge, blowing away the supposed tried-and-true silk glass rod we all have used for years. Have your students test the Fun Fly Stick to see if they can determine the actual charge it produces. Its really simple… Just charge a pith ball positive and then hold the Fun Fly Stick near the pith ball. Since the only real way to prove the charge on an object is repulsion, the pith ball will repel! Very cool!
Buzz Putnam, Physics teacher @ Whitesboro High School, NY