PIRA Classification: 5F20.45
Description: A wheatstone bridge is constructed using four light bulbs. Across the center of the bridge, LED arrows are used to display the direction of current through the center. When plugged in, the four outer (identical) light bulbs light while the central arrows don't. When one of the outer bulbs is unscrewed, one of the central arrows will light.
Special Instructions: None
Condition: Good
Setup time: 1 minute
Safety Issues: None