00:02
So we form this capacitor from the earth and a layer of clouds above it, and that 800 meters above the earth's surface.
00:15
And we know that the clouds have an area of one square kilometer, which when converted to square meters, is 1 ,000 squared meters squared, which gives us 10 to the 6th square meters.
00:40
And since the clouds are so close to the earth, we can assume that the earth's surface and the clouds are pretty much parallel.
00:48
And so this is the other plate of the capacitor, which will have the same area as the clouds.
00:57
So now if we want the capacitance, we say area times epsilon out over d, and we know all those values.
01:06
So we have 1 times 10 to the positive 6, 8 .85.
01:14
Times 10 to the minus 12 divided by 800 meters and this gives us 1 .11 times 10 to the minus 8 ferrets for the capacitance.
01:29
Now we want to know the maximum charge that the cloud can hold...