00:01
Okay, here we are going to review the photoelectric effect experiment.
00:06
So a reminder of what was inside that experiment apparatus.
00:11
There was basically a photo cell, which was a vacuum tube with two pieces of metal.
00:18
Towards one of the pieces of metal, you would shine a light source of a known color and a known intensity.
00:26
And then there was a second plate called the collector that would make a complete circuit outside the tube, an external circuit with a battery that you could vary, and an ammeter, which could be used to measure the current, the photo current.
00:48
And what we know happened as a result of this experiment, what we're going to talk about is what would happen in those measurements if you put in different, intensities of light.
01:05
So you could put in high intensity or low intensity or something in between.
01:13
But we'll just take a look at those two extremes.
01:17
And what people found out was that the so -called stopping potential, which was a reverse voltage needed to stop the current, that that did not depend on the intensity of light.
01:31
What would happen, is for low intensity, you would reach a certain maximum current once things had stabilized...