PHYS 103
Series and Parallel Circuits
REPORT 4
Take pictures of the setup when prompted by the assignment and put the photos into a Word
document. Label each step prior to the photo with the step in the instructions and include a
summary of your observations for each activity within the Word document.
Activity 1: Resistors in Series
All connected Removed clip Lamp is disconnected
Observation: The mini lamp lights up when the circuit is connected. When the battery clip is
disconnected from the batteries, the circuit is off.
Two Resistors in Series
R1 lamp is disconnected Removed clip All connected
Observation: When 2 lamps are connected, the light is dim. When you unscrew one lamp, the
other goes out. When the battery clip is disconnected from the batteries, the circuit is off.
All connected R1 lamp is disconnected Removed clip
PHYS 103
Observation: When all lamps are on the brightness is the same. When 1 lamp is disconnected, all
of the lamps turn off. The lights become more dim whenever more lamps are added.
Activity 2: Resistors in Parallel
R1 lamp is disconnected Removed clip All connected
Observation: When 2 lamps are connected in parallel they are equivalent to a one lamp circuit.
When one lamp is disconnected, the other lamp remains lit.
Three Resistors in Parallel
All connected R1 lamp is disconnected Removed clip
Observation: The lights in parallel shine brighter than in a series. When one lamp is
disconnected, the others remain on and do not brighten or dim.
Activity 3: Circuits with Resistors in Series and Parallel #1
All connected R1 lamp is disconnected R2 lamp is disconnected Removed clip
Observation: When all of the lamps are connected, R1 shines brighter than R2 and R3. When R1
was disconnected R
2
and R
3
turned off. When R
2
was disconnected, R
1
remained the same and R
3
became as bright as R1.
