The dark color reduces the amount of photons reflected. Photons that are not absorbed by the panel cannot be used to produce electricity.

What are Photovoltaic Cells Made From?

Silicon is the major material in the cells. Pure silicon crystals are poor conductors of electricity. Other elements are added to the silicon, such as, phosphorus and boron. When the energy from the sun hits the cell, the electrons in the elements begin to move around. The sun causes the panel to have a positive and negative side. This electrical difference causes electrons to flow through a diode.

What Factors Affect the Production of a Solar Cell?

The factors that most affect the production of a solar cells are the angle of the panel in relation to the sun, the peak wattage, the light intensity and the hours of sun exposure.

How is Wattage (or Power) Calculated?

The formula for power is   Power=Current X Voltage. Power is measured in watts, current in amperes and voltage in volts.

The Solar Science Kit has a small motor, photovoltaic cell and disc that works well in demonstrating this in a classroom or home setting.

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.

See the Oxygen molecules bubble and the indicator turn pink

Hydrolysis Water Splitting
Using a 9V battery, 2 electrodes and small gauge wire, you can split water into its component parts. This process is called hydrolysis. We add a small amount of salt to increase the conductivity of the water and an acid/base indicator to visualize the reaction.

The chemical formula of water is H2O. When the electrical current, produced by the battery, passes through the water,  the water will split and the two electrodes will bubble. Hydrogen will appear at the cathode and the oxygen at the anode. The acid base indicator around the cathode will turn blue (because the free OH molecules raise the pH) and the area around the anode will turn pink (because the free hydrogen molecules lower the pH).

Looking at the formula for water, there are twice as many hydrogen atoms as oxygen. When hydrolysis occurs, twice as many hydrogen bubbles will be released as oxygen. You can visually see extra bubbles at the point where hydrogen is being released.

Hydrolysis experiments can be quantitative (how much hydrogen and oxygen are released?) or qualitative (can I visually see the reaction taking place?)

Praying Mantid Eggcase

What is the difference between complete and incomplete metamorphosis in insects?

Incomplete and complete metamorphosis differ in the number of life cycle stages insects go through during their transformation from egg to adult. Complete metamorphosis has 4 life cycle stages and incomplete metamorphosis has 3 life cycle stages.

Complete Metamorphosis

Complete metamorphosis has four distinct life cycle stages: egg, larva, pupa and adult. Examples of insects that go through complete metamorphosis are butterflies, silkworms, mealworms and ladybugs. The larva can be worm-like, although you can still see the six legs. The larvae for moths and butterflies are called caterpillars. Maggots are the larval stage of flies. The larvae eat constantly and grow rapidly. A hard, protective case forms around the larva…this is the pupa stage. The pupa stage for a butterfly is called a chrysallis. The pupa stage for a moth is called a cocoon.

Incomplete Metamorphosis

Incomplete metamorphosis only has three life cycle stages: egg, nymph, adult. The nymph looks similar to, but a smaller version of, the adult. The nymph is also wingless. Examples of insects that go through incomplete metamorphosis are stinkbugs, earwigs, crickets, grasshoppers, cockroaches, ants and praying mantids.

How Do Geodes Form?

A geode starts off as a bubble or a void left by an animal burrow, tree root, or something else. Water is trapped inside of the void, which contains silica precipitation that has other minerals or elements present in it such as calcite, iron or manganese. The basic crystals of a geode are made of quartz (silicon dioxide) and are colored based on the contents of the surrounding soil.  Over thousands of years different layers of silica precipitation cool and create different layers of crystals. There is no way to tell what is on the inside of a geode without cracking it open. You can view the process of cracking open a geode below.

A species of the earthworm can be found on every continent in the world. They burrow through soil and help keep it healthy. Some species of earthworm can grow over 13 feet long, all though most are a lot smaller than that. Earthworms have been dissected in science rooms throughout the world, although if dissection is not an option, you can use lifelike plastic figures to represent the earthworm lifecycle.

Earthworms have both organs needed for reproduction; the term used for this is hermaphrodite. When earthworms mate they lay next to each other and pass mucus like substance that allows each worms organs to be fertilized. After the earthworms mate they form eggs inside their bodies, then the worms separate and form cocoons which seal when they rolls off of the worm. The cocoon is buried underground and the hardened walls protect the forming worm.

The worms hatch as smaller earthworms that lack reproductive organs; this is the main difference between newly hatched worms and the fully developed. The worms start to develop reproductive organs after they are hatched. They are able to use their reproductive organs at around 12 months. Earthworms can sometimes live for more than 10 years depending on the species. In the United States earthworms range in color from red to brown, and in other countries they can be blue or green.

Check Out These Large Earthworms

Magic snow is an absorbent polymer that is safe and non-toxic, it has the ability to expand up to 40 times its original volume. The snow starts out as a simple powder that looks similar to sugar or salt. The magic happens when water or other liquid is introduced to the magic snow, which quickly expands to absorb the liquid.

How is it Used?

Hollywood uses it for special effects, many people use it to decorate for parties, and thanks to its low price you can use
magic snow for fun. When using magic snow, use it on a dish, bowl, cup, test tube, or anything else that will help you contain the magic snow. First place the magic snow into the container of your choosing, next sprinkle a small amount of magic snow into the container. Then add a small amount of water and watch it grow. Use more in the following trials once an idea of the amount the magic snow expands is gained.

Example





Do not let magic snow into drains or pipes; it will expand causing them to clog. The best way to dispose of magic snow absorbent material is to put it in a plastic bag and then in the trash. Do not rinse the container you use for magic snow creation in the sink, even a little can cause clog. However if you do accidentally clog a drain, a small amount of bleach will clear the drain.

Ants are insects that evolved from wasp-like creatures over 100 million years ago. Today there are over 12,000 species of ants that have been classified.

Ants form colonies that range in population from a few dozen living in small natural cavities to millions that live in larger structures they build in the ground. The colonies consist of three types of ants. Sterile, wingless females, fertile males, and fertile females referred to as queens. The sterile female ants serve as soldiers or workers in the colony.

Ants work together in colonies to build their habitat and recreate. The process can be fascinating to watch for children and adults alike. Due to the fact that most ant colony behavior takes place beneath the ground, humans must use ant habitats or ant farms to observe ant colony behavior.

Ant Farming

The ant farm is designed to study ant and ant colony behavior by offering a great observation tool for the classroom or just for fun. Myrmecologists study ant behavior, and with an ant farm you can take a look into the world of myrmecology (the study of ants).

Ant Farm Types

The Ant Farm by Uncle Milton is a classic ant farm that has a green farm scene with a clear viewing pane surrounded by a green frame. The farm is usually filled with sand, dirt, or other media. These ant farms have a low price point making them accessible to classrooms and families of all budgets. In order to properly care for your ants, you will need to open the ant farm and make sure the ants have food and water. The down side is that this increases the chances of the ants getting out of the farm and into places you do not want them.

In recent years the Ant Farm has been modernized with improvements to visibility. A modern alternative ant farm is the AntWorks Illuminated Habitat

AntWorks Illuminated Habitat

The AntWorks ant farm is completely see through thanks to a gel that NASA developed when studying ants tunneling at zero gravity. The gel holds nutrition and water so that you do not have to provide the ants with nourishment. The AntWorks Illuminated Habitat is available with either red, green, or blue gel. The setup also includes LED lighting in the base so that you can view the ants at night. All of this is housed in a tightly sealed 6.5L x 6.0W x 1.25D clear acrylic habitat to minimize ants escaping into your house, lab, or classroom.

Set Up

Set up of the green AntWorks Illuminated ant farm was easy using the provided instruction manual. After assembling it and testing the LED lights the next step was to go out and find some ants. There are two options for getting your ants, you can either send in the coupon provided with the kit or find your own ants. After finding the ants, they were put into the ant farm which was covered with a towel for 3 days to allow the ants to get used to their new home. After adjusting to life on the ant farm the ants have created a spectacular tunnel system that looks even better in the dark with the LED lights on. They are fascinating creatures to watch and learn from.

For more information, Wikipedia has in depth information about insects including ants . You can always call Heath Scientific as well.

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.

Enough about the details lets take a look at the Warblettes in action!! As mentioned they are able to absorb 200 times their volume in water. Our experiment compares the warblette, aluminum foil from a chewing gum package,  and a piece of paper towel. This will show the differing amounts of absorption between the water marble and these other household items.

First the paper towell, foil, and the warblette were placed in water bottle caps, then each cap was filled with water.  (Note that we are using bottle caps as they are easily accessible in the home.  If you wish to measure liquid absorbtion in milliliters, a beaker or test tube will need to be used).  The items were left alone for 8 hours allowing them to absorb as much water as possible.

The picture below shows all of the items after 8 hours of absorption time. As you can see the aluminum foil absorbed no water, which was expected as metal is a virtually non-absorbent material. The paper towel absorbed a little more than half of the water in the cap. Paper towels are designed to clean up spills so it makes sense that this would be the case. Finally the warblette absorbed all of the water available in the cap, we even filled it a second time and it absorbed this too! The warblettes actually lock the water away so that they are not wet to the touch like the paper towel is.

Here is a picture of the warblette before the introduction of any water, as you can see it is very small in comparison to a dime.

This is the warblette at the end of the experiment; note the drastic size change after the absorption of water.

Warblettes have superior absorbent properties when compared with the aluminum foil and paper towel. This is an example of an easy and fun experiment that can be done with simple household items. The lab activity book offers more challenging experiments that are better suited for science fairs and classroom experiments. To find more experiments like these visit Heath Scientific, a family owned and operated company, which has been providing teachers, parents and students with educational supplies for more than 20 years. They offer warblettes and many other science supplies, science fair kits, and other fascinating products.