Video: Watch this demo
Description: This demonstrations shows that a large capacitor can light a bulb for several seconds
- Digital Power Supply
- SPDT switch
- 1F capacitor (rated at 5Vmax)
- 6.3V Bulb
- Small c-clamp
- Wires and alligator clips
- Set up the demo according to the configuration in the photos. Wires are color coded to show where each wire connects. Use the black c-clamp to hold the switch in place.
- Turn on digital power supply and tune to your desired voltage. Do not exceed 5V
- Test to make sure everything works correctly. The bulb should start off bright and dim as the capacitor charges, and should do the same as the capacitor discharges.
- When the professor is done, make sure the capacitor is discharged.
- Move the switch to the charge position and wait for the capacitor to charge (the current will be zero when it is fully charged).
- Move the switch to the discharge position and note that the capacitor lights the bulb, and the bulb gets dimmer as time goes on.
- Repeat if desired.
Concept: Capacitors are electrical components that store charge for use as a power source. Because they only store a finite amount of charge, they can only supply voltage for a limited time. This concept is illustrated in this demo by using a charged capacitor to power a light bulb, but the bulb will eventually die because its power supply is limited.