What is a Generator?

When a magnet moves toward a metal object, the electrons in the metal move. As a result, when a magnet moves near a copper wire, electrons in the copper move. Generators use this principle to convert mechanical energy (the rotation of a wire coil,or rotor around a magnet) into an electrical current (electrons flowing through the wire). A motor performs the opposite function by converting electrical energy into mechanical energy. For the most part, all generators work the same. The item that separates them is, “What turns the rotor?”

Windmill Generator Kit

 Energy Conversion in a Windmill 

 Obviously, in a windmill, the wind is rotating the wire coil around the magnet. This generator is taking the kinetic energy from the wind and converting it to electrical energy.

Windmills are rated based on output power (watts), working voltage (volts), start up windspeed (mph), survival wind speed (mph), rated rotation of the blades (rpm) and the diameter of the blades  (also called the rotor). In general, the larger the rotor diameter the more wind that is intercepted and the more electricity produced. There are do-it-yourself plans available for building your own windmill. No waste or pollution is produced during this process.

When discussing this in the classroom or entertaining your children on the weekend, there are some small demonstration kits available. The Windmill Generator from 4M Kidz Labz TM is an excellent activity.

Dissecting owl pellets is a fun and educational method of analyzing predator / prey relationships and for learning basic dissection techniques.

What is an Owl Pellet?

An owl pellet is the portion of an owl’s prey that has not been digested. Owl’s swallow their prey whole (they don’t have teeth to chew) and the feather’s, fur, bones and other undigestible parts are regurgitated by the owl.

How Does the Owl Pellet Form?

When the prey is swallowed, it travels through the esophagus and into the first part of the stomach, the proventriculus. Unlike other birds, the owl does not have a crop to store the food. As a result, the prey enters directly into the digestive tract. This part of the stomach has enzymes and acids (like our stomachs) to aid in digestion. From the proventriculus, the food travels to the second part of the stomach, the gizzard. The gizzard is a muscular organ that grinds the food and ”filters” undigestible parts from traveling into the intestines.

The pellet is formed from the hair, bones or feathers that are left in the gizzard. The pellet will take several hours to form and several more before it is regurgitated. The owl cannot eat again until this pellet is expelled.

Does the Regurgitation of the Pellet Benefit the Owl?

Yes.  Many scientists believe that this regurgitation of the pellet keeps the upper digestive tract clean.

Bacteria can be differentiated based on how they react to a a procedure of dying cells called Gram stain. Bacteria are divided into a group that turns purple (gram positive) and a group that turns red (gram negative). Bacteria that are gram (+) include Staphylococcs, Streptococcus, Bacillus and Micrococcus. Gram (-) bacteria include E.coli and Salmonella. The Gram staining procedure is as follows:

Gram Staining Bacteria Procedure
1.Place a drop of distilled water on a slide and, using a swab or inoculating loop, mix the bacteria with the water an smear the mixture on the slide. The mixture will appear cloudy. Using a flame, heat fix the bacteria to the slide (pass the slide through the flame a few times to “dry” the bacteria and affix it to the slide).

2. Using a dropper, add crystal violet to the slide. Let stand for 1 minute.

3. Add iodine to the slide. Let stand for 3 minutes.

4. Decolorize the sample with alcohol. Let stand for 30 seconds.

5. Counter stain the sample with safranin. Let stand 1-2 minutes. Using a dropper, rinse with distilled water.
Gram Staining Results
Gram positive bacteria will appear purple under the microscope. They have a single, thick cell wall. The crystal violet and iodine combine to attach to this wall. The decolorizer (alcohol) dehydrates the cell wall, causing the pores to close, trapping the stain inside. the safranin added in the final step, does not penetrate the wall.

Gram negative bacteria will appear red. The have a cell wall and additional thin layers of fatty sugars. The decolorizer easily penetrates these thin sugar layers, washing away the crystal violet – iodine chemical (purple color). The safranin in the last step attaches to these layers and appears red.

In a previous post on warblettes, we conducted a small experiment demonstrating the absorption characteristics of warblettes.   There is a small summary below that you can use as a refresher, or you can view the actual warblette experiment.

Warblettes Lab Activity

As mentioned in the previous post, warblettes are co-polymers that absorb up to 200 times their volume in water.  Warblettes are perfect for science fair experiments, in the classroom, or just as a fun activity for your family. Warblettes, which are sometimes referred to as water marbles, are non-toxic and come in clear, red, blue, green, and yellow colors.

The basic absorption experiment we posted on warblette absorption is a simple experiment that uses household objects.  Warblettes can be used for much deeper science and educational learning.  Heath Scientific has created a lab manual for this purpose.

The warblette lab activity book has activities for every age student. There are 13 activities ranging from math and graphing to cellular biology. You can use warblettes to demonstrate potential and kinetic energy, change over time (graphing), man-made and natural polymers, and light refraction. The labs include explanations and procedures. If needed, modify the activities to fit your students abilities or needs.

The Labs Cover:

1.) Calculating Volume – Math
2.) Observation Skills
3.) Polymers and Water Absorbtion
4.) Absorption of Household Liquids
5.) Water Absorption and Time
6.) Water Absorption and Temperature
7.) Advanced Measurement – Volume, Calipers, Averaging, and Reading Charts
8.) Graphing – Line Graph
9.) Potential Energy – Comparing Diameter to Rolling Distance
10.) Varying the Height of an Inclined Plane
11.) The Effects of Acidity on Water Absorbtion
12.) Light Refraction
13.) Density

Both the warblettes and the lab activity book are available at Heath Scientific, which has been providing educational supplies for over 20 years.

This post takes a look at the Hydro-Splitter Kit offered by Heath Scientific. The Hydro-Splitter Kit is a science fair project for kids that educates them about electricity and the electrolysis of water.

Other projects similar to the Hydro-Splitter are also available from the Heath Scientific website. The website offers science supplies as well as other science projects cover a wide range of topics from carbon to light and optics kits. These kits offer a cost effective way for parents to enrich their children’s minds while having fun at the same time.

General Information

Water is made up of twice as many hydrogen molecules as oxygen molecules; this is why the chemical formula is H2O. Electricity breaks this formula down when introduced into water. The molecules split with hydrogen appearing at the cathode and the oxygen will mix with one hydrogen molecule making hydroxide.

Supplies Needed

- 1 Beaker
- 2 Carbon Rod Electrodes
- 1 Acid/Base Indicator
- 3 Alligator Clip Wires
- Salt
- 2 Droppers
- 9 Volt Battery- not included in the Hydro-Splitter Kit

Experiment Procedure

The carbon rod electrodes are connected to the battery with the alligator clip wires. Fill the beaker with 200 milliliters of water along with 25 drops of acid/base indicator and a pinch of salt. Adding a second 9 Volt battery can increase the speed of the reaction.

Results

There will be more hydrogen molecules than oxygen in the water and the electrode that the hydrogen is drawn to will have more bubbles. The water around this electrode will be blue; the water around the other electrode where the oxygen is drawn will be pink. This kit allows for a cost effective way to explain the concepts of electricity and voltage.

Founded by Pat and Heath Nichols, Heath Scientific is a provider of educational supplies located in Cedar Hill, Texas. Major suppliers of Heath Scientific include AntWorks, Thames & Kosmos, Uncle Milton, and Can You Imagine. If you are interested in hosting a school fundraiser, or obtaining science related educational tools, contact Heath Nichols at Heath Scientific by email at heath@heathscientific.net or by phone at (972) 291-4223.