The first part of this activity, “battery & bulbs”, was first introduced into the science education curriculum in the post-Sputnik era (1957-1980) when the US first felt it was losing ground in STEM education. The staying power of this activity is a testament to its elegance. For this project, “battery & bulbs” is a lead-in to thinking about household circuits. Electric energy is so pervasive in our society we do not think about it until it is not there. So much of what we do depends on generated electricity (see generation video on this site) or batteries (see classroom video on the Prius on this site) that it is rare to think of a modern activity or task that does not use electrical energy.
House circuits depend on generated electricity delivered through a circuit breaker panel, usually in the garage or utility room or closet. Electrical energy runs through multiple circuits from the panel to different rooms in the house and back again through the panel returning to the generating station. Circuits for a home are most commonly designed for 20 amps at 120 volts, but this varies (see Circuit Breaker Panel activity: http://theselsproject.org/circuit-breaker-panel-activity/). [SAFETY WARNING] This is enough power to give you a severe shock. Someone who understands home circuits and electrical energy should supervise anytime you are working with exposed house circuits.
One reason for learning about electricity in school science or technology classes is because these ideas are directly useful in your life now! Understanding how electricity is generated, distributed, and used inside a home, school, or work can be of great benefit to you now! This knowledge can keep you safe, keep things working, and perhaps be knowledge useful in a job, earning you more money.
3 or more C cell batteries
3 or more flashlight bulbs
10 or more pieces of wire with ends bare
3 or more switches
Holders for batteries and bulbs
Optional items: Differential Voltage Probe, Current Probe
The first step for this activity is to download the Circuit Activities activity sheet (http://theselsproject.org/wp-content/uploads/2013/04/Circuit-Activities-bat_bulb_wire-etc.pdf). The activity sheet poses a sequential set of problems to be solved using one or more batteries, one or more bulbs, and wires. The problems get progressively more difficult. These problems are models of home circuit situations. Some of the problems also compare parallel and series circuits. Once you have completed these problems, you should be able to explain whether homes are series or parallel circuits.
The very first activity asks that you try making the bulb light holding only the battery and ONE wire. This is the classic activity that has been done in schools for over 40 years. It is not as easy as you might think. After working on this problem for a while, compare your efforts to the diagrams.
There are a large number of problems on the worksheet including problems to test your self. The first problems will teach basics about electric circuits. The latter problems require much more sophisticated knowledge about electrical circuits.
Electronic circuit: series, parallel.
Next Generation Science Standards
Scientific and Engineering Practices:
– Obtaining, evaluating and communicating information
– Energy and matter: Flows, cycles and conservation
- Provide evidence for why you think house circuits are parallel or series.
- Explain the meaning of a “short circuit with examples.
- Even though you cannot see in the walls of your house, using the knowledge from solving the problems in this activity, make a diagram of circuit that delivers electricity from the circuit breaker to the outlets and lights in your room. Explain how the electricity flows from the circuit breaker and back.