Electricity & Circuits

Allow for a range of responses and diagrams. Look for the idea of a completed circuit.

As electricity moves through the wire in the bulb, the electricity is transformed into thermal energy that heats up the filament in the bulb, causing the heated filament to glow.

Metals like copper, aluminum, gold, and silver conduct electricity.

The metal wire allows the electricity to flow, but the plastic coating prevents the electricity from transferring to another conductor.

Holiday lights are connected in a series circuit, which means every light is connected together and to the source of electricity.

Volts are a measure of potential energy. The higher the volts, the more potential energy is stored.

Electricity is the flow of electrical energy from one place to another.

For electricity to flow, it needs a closed path from the source, through a conductor, and back to the source.

In a series circuit, you could turn on and off all the lights or devices at the same time, instead of turning each one on and off separately. In a parallel circuit, each light or device has its own path to the source, so you can control each one separately. If one light or device goes out, the other devices in the circuit are not affected.

You could use a higher or lower volt battery to control the brightness of a light bulb or the spin of a motor in a circuit. Volts are the measure of potential energy in a battery; the higher the volts, the more potential energy. Or you could add or remove resistors from the circuit, as resistors reduce the amount of electricity flowing through a circuit. Or you could add a potentiometer to the circuit and change the amount of electricity flowing by adjusting a knob or a slider. Students might even mention using a transistor in an integrated circuit to boost the electrical signal.

Circuit boards allow all of the components (fuses, LED, capacitors, resistors, transistors, potentiometers, etc.) to be integrated into a small package. Minimizing circuit boards has been a major advancement in electronics. Using a circuit board makes it easier to switch components as needed.

Electrical engineers design circuits for a vast range of things—robots, video games, electric cars, computers, phones, prosthetics, power grids, drones, space shuttles, and more.