00:01
So in this problem, we're given an example of power outputs from the united states power plants.
00:07
And we are told that they have an efficiency of 33 % and that the power output is 2 times 10 to the 11.
00:17
So in order to find how much power is input, we first write down the efficiency equation.
00:28
So in this one, we're going to use the power, which is the power input.
00:35
Over the power output plus the input.
00:41
So when we plug in the efficiency values, this gives us 33 % efficiency is equal to 1 minus the input over the input plus the 2 times 10 to the 11, which is what we're told is the output.
01:08
So then solving for this, we can multiply both sides, by pc plus 2 times 10 to 11.
01:22
So we'll cancel these out here and then multiply it by this side.
01:25
So we can write that.
01:28
0 .33 times p .c.
01:39
10 to the 11.
01:40
And this is equal to 1 minus pc.
01:47
So then just do some basic algebra here.
01:51
Add pc to the other side.
01:52
So we get 1 .33 pc is equal to 1 minus.
02:03
And then we can have 2 times .33.
02:08
So we have 0 .66 times 10 to the 11...