P = IV

Return to Resistance, EMF, and Current

This demo shows the relationship between power, current and voltage using a 12 V power source, 2 meters (1 for voltage and 1 for current), and a light bulb stand with three different wattage 12 V light bulbs. Light bulb 1 is a 25 W incandescent bulb, light bulb 2 is a 75 W incandescent bulb, and light bulb 3 is a 12 V LED bulb. Switching on individual bulbs will show the current and voltage provided for each bulb. To measure the current of the led bulb, you have to switch the meter units to milliamps instead of amps

Locations:

• Power source: Sh. K-2
• Meters: Sh. K-1
• Meter units: Sh. K-1
• Light bulbs: Dr. 113
• Light bulb stand: Sh. O-2