Today the students learned about electrical engineering. The instructor used a waterwheel as a metaphor for an electrical circuit. Each of the parts that you needed to turn a waterwheel has a similar function to a part of an electric circuit. For example, the water is like the current of electricity, the hill the water starts from is like the battery (it provides the energy of the current), the pipes or channels of the river are like the wires and connections of a circuit (they direct the electricity and limit its flow), and the waterwheel and work it is doing are like the lightbulb or motor that uses power to run. The students also looked at the different things that could be measured on a waterwheel, like how steep the hill is, how fast the water is moving, and how much grain can be ground every day. We then compared those to the voltage (how much the electricity wants to move), the electrical current (how much electricity is going through a wire), and the amount of power that our circuit produces (measured in watts).
After learning about the parts of an electric circuit and how they work the students were given the chance to build some circuits of their own. Using a breadboard as a "landscape" that they could build their circuit on, the students used a battery, wires, an LED (Light Emitting Diode), which is just a small lightbulb, and a resistor (to regulate the current of their circuit and keep the LED from burning out), they built a simple circuit to light up an LED.
After all the students had successfully built their circuits, they were ready to learn how to build a more complex circuit using some new components. They learned about a capacitor, which is like a glass that uses "water" (electric current) to get up to a higher height (more voltage), then dumps out the water and starts again (oscillating between a high and low current). A 555 timer chip was also introduced, which switches the output on and off as the capacitor charges and discharges. With this chip and capacitor the students made the LED flash on and off, and they experimented with different sized capacitors to make it flash at different rates. Quite a few of the students said that they didn't know that there were so many parts in a circuit and that they felt like they understood circuits much better after the workshop.