When you have more than one battery or more than one light bulb (or bell or buzzer or other load ), they can be arranged in two different ways:
In Series means that they are lined up one after the other, in a straight line.
In Parallel means that they are lined up next to each other.
Series circuits
are easier to wire, but have some problems and often need more power. Try
these experiments.
A. Create a series circuit.
-- make a
circuit that will blow up a light bulb. Drag your blown up bulb to the
side (so you can use it later), and get rid of everything else... then
get:
- 3 9-volt batteries
- 5 christmas tree lights
- 1 switch
Notice that you have to connect the batteries from the + on one battery to the - on the other. When it is wired up, turn the switch on.
1. What happens
to the lights? __________________________________
Turn the switch off. Get rid of one of the lights, and replace it with the broken bulb. Turn the switch on.
2a. What happens to the lights? ________________________________
b. Why do you think this happened? _____________________________
________________________________________________________
B. Make a parallel circuit.
You’ll need:
- 5 Christmas tree lights
- one 1.5 volt battery
- one switch
- the broken light bulb
When it is
wired up, turn the switch on.
3. What happens to the lights?_________________________________
Turn the switch off. Get rid of one of the lights, and replace it with the broken bulb. Turn the switch on.
4a. What happens
to the lights? ________________________________
b. Why do you think this happened? _____________________________
________________________________________________________