Transcript capacitor lab directions

•Two basic types
•Ceramic disk
•Electrolytic
•Has positive
and negative
sides
•Farads – unit of measure (F)
•Microfarads(uF) and picofarads (pF)
•Cans have value written on them
•Ceramic use a code. Shorthand because not enough room for entire value
IMPORTANT!
• You MUST put an electrolytic
capacitor in correctly with the
+ and – sides in their proper
places.
• The – side is clearly marked
on a band with – signs.
-
You will need the following parts from your kit:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Breadboard
1000 ohm resistor (brown, black, red, gold)
330 ohm resistor (orange, orange, brown, gold)
1000uF capacitor
100uF capacitor
1 LED (light emitting diode)
9 volt battery lead
2 wires
9 volt battery
Use this schematic to construct the experiment.
330 ohm
1000 ohm
Flow of current
+
+
9 volts
-
Flow of current
Copy and label all the components of
the schematic in your notes.
Quick Check:
Your circuit should like this one.
See next slide for a close up
Check wiring with this close up
This is the (-) side
All 3 in same
row on (+) side
1.
2.
3.
4.
5.
6.
7.
8.
Start with the 1000uF capacitor in place.
Connect the 9 volt battery.
Observe the brightness of the LED.
Disconnect the 9 volt battery.
Observe what happens to the LED.
Replace the 1000uF capacitor with the 100uF
capacitor.
Reconnect and then disconnect the 9 volt battery
Observe what happens to the LED.
Troubleshooting:
1. If the LED’s do not light up, check to make sure they in correctly.
2. Check the battery. Does it have voltage?
3. Are there any breaks in the circuit?
4. Is the capacitor in the right way?
1.
2.
3.
4.
5.
6.
What happens when the power is applied to the circuit by
plugging in the battery?
What happens when the power is removed from the circuit by
unplugging in the battery?
How are the results different using the 1000uF capacitor
compared to the 100uF capacitor?
Which capacitor stores more energy, the 1000uF or the
100uF? How can you tell?
Which kind of capacitors appear to have a greater capacity,
the ceramic or electrolytic? (Look in your kit, which have a
larger size? That’s a good indicator!)
Ceramic capacitors are not polarized. Electrolytic are.
Which side is the anode(+) side and which is the cathode
side (-) of the electrolytic capacitors? Name 2 ways you can
tell.
Use this schematic to answer the questions.
330 ohm
1000 ohm
Flow of current
+
+
9 volts
-
Flow of current
7. What is the purpose of the 2 different resistors in the
circuit? Does it appear that electricity is flowing through
both the capacitor and the LED when the battery is
plugged in? Where does the electricity flow when the
battery is unplugged?
8. In complete sentences, write what you learned about a
capacitor in a circuit.