Diode Twirl
![A light plugged in to an outlet](/media/libraries/college-of-science-and-engineering/physics/images/demo-images/DIODE1A.jpg)
PIRA 5L30.20
The bi-colored diode shown at left is connected up to a current limited transformer. If the diode is waved back and forth or swung in a circle as shown at right, the alternating nature of wall current can be demonstrated. The lights need to be dimmed for this to show up in a large class.