AMSTI CircuitsLesson 11

Overview•You will build 2 kinds of circuits: a series

circuit and a parallel circuit.

•Will use the same material for both circuits.

•Examine the differences between these 2 circuits to identify properties of series and parallel circuits.

Materials

•Box with 2 batteries in holders, 2 bulbs in sockets, and 3 wires

•Another 6 inch wire

•Refer to circuit diagram created during last lesson.

•Create the circuit looking at your diagram.

•Give diagram to a partner and see if he/she can create your circuit.

•Predict which bulbs you think would burn brighter.

•Predict which bulbs you think would burn longer.

•Use the circuit diagrams to make the circuit. Each partner will make one of the circuits.

•Compare the brightness of each circuit with a standard bulb, classifying it as “dimmer”, “about the same,” or “brighter.”

•Look at the differences between the 2 circuits and discuss what you notice.

Series Circuit

Series circuit•Electricity has only one path to travel

from one point on the circuit through the wires, batteries, and bulbs and back to the starting point

•Voltage across the bulb increases

•Bulb glows brighter than it did when only one battery was used

•Batteries will drain more quickly

Parallel Circuits

Parallel Circuits

•Electricity travels along more than one path around the circuit

•Brightness of bulb same as with one battery

•Bulb burn longer

•With a partner create a series and parallel circuits using 2 bulbs and 1 battery

•Compare the series and parallel circuits. What happened?

•Draw the circuits.

Bulbs wired in Series Circuit

Bulbs wired in Series Circuit

•2 bulbs with 1 battery

•Burn with uniform brightness

•Not as bright as one bulb alone

Bulbs wired in Parallel Circuit

Bulbs wired in Parallel Circuit

•2 bulbs with 1 battery

•Each bulb burns as brightly as one bulb

•Can unscrew one bulb does not make the other bulb go out

•Electricity travels in independent paths through each bulb

Extensions

Science Fair Experiment

• Make a series circuit, parallel circuit, and a standard circuit with one bulb and battery.

• Use this experiment to see which circuit will last the longest.

• Check in morning and evening each day.

• Each day write what noticing.

• After all 3 bulbs are “burned out,” discuss the results.

• What do you think caused the bulbs to go out? (bulb burned out or battery drained)

• How could we check these ideas? (refer back to the troubleshooting strategies to see whether the bulb or battery was responsible)

The End!!!