## Description

### Student Experiments

### Explore key variables voltage, current and resistance

- Measure the voltages of new and used alkaline batteries with a multimeter.
- Try lighting an LED, spinning a motor or buzzing a buzzer with new and used batteries.
- Estimate the minimum voltage required for each component. Research the answers online.
- Connect batteries in series to light an LED. Measure the separate and combined voltages of the batteries.
- Observe the voltages of batteries connected in series: ADD their voltages.
- Measure the voltage across components connected in series and discover the idea of a voltage divider.
- Stack pennies, galvanized washers and vinegar dampened paper to construct a model of the first batteries every made.
- Measure the voltage as they add to the stack.
- Read about the first voltage piles and learn about voltage as “electrical” pressure analogous to water pressure in a hose.
- Make potato batteries and explore connecting them in series and parallel to buzz a buzzer and make predictions and measurements.
- Learn to measure current with the multimeter and use it to measure the current from their potato batteries when connected in series and in parallel.
- Discover and state Kirchhoff’s VERY simple law: Current IN = Current OUT.
- Define current using an analogy to water flowing in a hose.
- Make the simplest of electron movement detectors to detect current using only a wire, a compass and a battery.
- Define Watts (P), a unit of power, as equal to voltage (V) multiplied by current (I). The equation is P=V x I.
- Investigate the wattage used by common household appliances and discuss energy choices.
- Make a very simple light dimmer with a graphite pencil and measure and explore the idea of resistance.
- Make and use a continuity tester with just a buzzer, a battery and 3 alligator leads. Learn to use the continuity tester on the multimeter.
- Make circuit puzzles and challenge others to find the hidden connections using the continuity testers.
- Use the water hose analogy, once again, to understand resistance as the slowing down of the flow of current in a circuit.
- Learn the color coding for electronic resistors. Use online apps and the multimeter to determine the resistance of a resistor.
- Explore how wiring know-how relates to resistance and fire safety in homes, schools and offices.
- Learn Ohm’s Law (V=I x R). You only need to know how to multiply and divide to use it. If you know any two of these variables, you can calculate the third one.

### Apply this knowledge to build some simple, appealing circuits using a breadboard:

- Students build a touch sensor on a circuit board using three electronic parts: a resistor, an LED and transistor connected to a battery
- Students learn that transistors are simple switches WITH NO MOVING PARTS. They are either ON or they are OFF.
- Students make a simple LED flasher which uses 2 resistors, an LED, 1 transistor and now an electrolytic capacitor.
- Students explore how a capacitor works.
- Students build a flip-flop flasher using familiar components with simple instructions.
- Students build a “lie detector” that is tuned to detect changes in skin moisture.

#### Requires 1 9V D cell battery per student and additional AA, AAA, C and D cells, used and new to share.

Pennies, galvanized washers, potatoes or lemons, aluminum foil, vinegar, salt, galvanized nails, copper roofing nails, compass

The online teacher lesson plans coordinate the ScienceWiz Electronic projects with web-based materials.

These include animations, videos, interactives and assessment materials.

Supplemental internet materials allow students to progress at their own pace and to their own level of interest and detail.

The web contents are periodically updated by scientists and educators.

These Teacher’s Packs are designed so that students have their own readers and materials. Extensions to the primary projects are feasible as there are sufficient supplies for all. This Pack consists of largely non-consumables and uses robust components designed for years of classroom use. Replacement parts can be purchased on this website or by contacting ScienceWiz™.