Series and Parallel Circuit Lab
Purpose
Part I – Series Circuit
How does adding more loads (light bulbs) to a series circuit affect the brightness of the bulbs?
Part II – Parallel Circuit
How does adding more loads (light bulbs) to a parallel circuit affect the brightness of the bulbs?
Materials



circuit board with three light bulbs
8 alligator clips
power source
Procedure
Part I – Series Circuit
1.
2.
3.
4.
5.
6.
7.
8.
9.
Draw a schematic diagram for one bulb in series.
Using the circuit boards, hook up one bulb in series.
Turn the power source on and turn the power knob to half way.
Note the brightness of the bulb.
Turn off the power source without changing the power knob (this needs to be kept
constant)
Draw a schematic diagram for two bulbs in series.
Using the circuit boards, hook up two bulbs in series.
Turn on the power source and record how the brightness of the two bulbs compares to the
brightness of one bulb in series.
Repeat steps 5 – 8 for three bulbs in series.
Part II – Parallel Circuit
As above (with series) for one, two and three bulbs hooked up in parallel.
Analysis
1.
What happened to the brightness of the light bulbs connected in series as you added more
light bulbs to the circuit?
2.
Why do you think the light bulbs behave that way in a series circuit?
3.
What happened to the brightness of the light bulbs connected in parallel as you added
more light bulbs to the circuit?
4.
Why do you think the light bulbs behave that way in a parallel circuit?
Series and Parallel Circuit Lab
Purpose
Part I – Series Circuit
How does adding more loads (light bulbs) to a series circuit affect the brightness of the bulbs?
Part II – Parallel Circuit
How does adding more loads (light bulbs) to a parallel circuit affect the brightness of the bulbs?
Materials



circuit board with three light bulbs
8 alligator clips
power source
Procedure
Part I – Series Circuit
1.
2.
3.
4.
5.
6.
7.
8.
9.
Draw a schematic diagram for one bulb in series.
Using the circuit boards, hook up one bulb in series.
Turn the power source on and turn the power knob to half way.
Note the brightness of the bulb.
Turn off the power source without changing the power knob (this needs to be kept
constant)
Draw a schematic diagram for two bulbs in series.
Using the circuit boards, hook up two bulbs in series.
Turn on the power source and record how the brightness of the two bulbs compares to the
brightness of one bulb in series.
Repeat steps 5 – 8 for three bulbs in series.
Part II – Parallel Circuit
As above (with series) for one, two and three bulbs hooked up in parallel.
Analysis
1.
What happened to the brightness of the light bulbs connected in series as you added more
light bulbs to the circuit?
2.
Why do you think the light bulbs behave that way in a series circuit?
3.
What happened to the brightness of the light bulbs connected in parallel as you added
more light bulbs to the circuit?
4.
Why do you think the light bulbs behave that way in a parallel circuit?