[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.06,0:00:01.86,Default,,0000,0000,0000,,On the bottom because I can\Nsee that you couldn't see it.
Dialogue: 0,0:00:02.89,0:00:07.48,Default,,0000,0000,0000,,Okay, when we first started this\Nproblem we were given Vs Is and that
Dialogue: 0,0:00:07.48,0:00:12.95,Default,,0000,0000,0000,,the resistances and we were asked to find\Nall of the currents which we just did.
Dialogue: 0,0:00:12.95,0:00:16.95,Default,,0000,0000,0000,,Now we'd like to be able to find\Nthe power from this particular source.
Dialogue: 0,0:00:16.95,0:00:18.61,Default,,0000,0000,0000,,Well, how do I find power?
Dialogue: 0,0:00:18.61,0:00:23.13,Default,,0000,0000,0000,,Let me look in my toolbox of\Npossible equations to use.
Dialogue: 0,0:00:23.13,0:00:25.19,Default,,0000,0000,0000,,Here we used Kirchoff's Law.
Dialogue: 0,0:00:25.19,0:00:29.96,Default,,0000,0000,0000,,And here is how we, and\Nthis is how we calculate power.
Dialogue: 0,0:00:29.96,0:00:34.31,Default,,0000,0000,0000,,So when I had Kirchhoff's Law I\Nknew my current source and
Dialogue: 0,0:00:34.31,0:00:38.44,Default,,0000,0000,0000,,my voltage source and my resistance and\NI was able to calculate current.
Dialogue: 0,0:00:38.44,0:00:42.39,Default,,0000,0000,0000,,Now, if I want power,\NI need to have one of these three things.
Dialogue: 0,0:00:42.39,0:00:45.02,Default,,0000,0000,0000,,I need to have voltage\Ndifference in the current, or
Dialogue: 0,0:00:45.02,0:00:48.52,Default,,0000,0000,0000,,voltage difference in resistance,\Nor current in resistance.
Dialogue: 0,0:00:48.52,0:00:52.84,Default,,0000,0000,0000,,Here I have,\Ncan I have voltage difference and current?
Dialogue: 0,0:00:52.84,0:00:57.13,Default,,0000,0000,0000,,I certainly have current, I've got I but\NI don't have voltage difference.
Dialogue: 0,0:00:57.13,0:00:59.45,Default,,0000,0000,0000,,So how can I get voltage difference?
Dialogue: 0,0:00:59.45,0:01:02.21,Default,,0000,0000,0000,,Well, there are several tools that I\Nhave for getting voltage difference.
Dialogue: 0,0:01:02.21,0:01:04.54,Default,,0000,0000,0000,,And this is actually the one\Nthat I'm going to use.
Dialogue: 0,0:01:04.54,0:01:07.88,Default,,0000,0000,0000,,If I have, oops, is that the one I want?
Dialogue: 0,0:01:07.88,0:01:11.90,Default,,0000,0000,0000,,Sure, voltage difference is\Ncurrent times resistance.
Dialogue: 0,0:01:11.90,0:01:14.18,Default,,0000,0000,0000,,So I have current, and I have resistance.
Dialogue: 0,0:01:14.18,0:01:17.44,Default,,0000,0000,0000,,Right here I have current and resistance,\Nso I can get voltage difference.
Dialogue: 0,0:01:17.44,0:01:20.18,Default,,0000,0000,0000,,So watch how I'm going\Nto solve this problem.
Dialogue: 0,0:01:20.18,0:01:25.41,Default,,0000,0000,0000,,I'm going to use Kirchoff's Law with\Nmy known sources to find current.
Dialogue: 0,0:01:25.41,0:01:32.34,Default,,0000,0000,0000,,And then I'm going to use my current and\Nresistance to find voltage difference.
Dialogue: 0,0:01:32.34,0:01:34.82,Default,,0000,0000,0000,,And then, kind of here in a line,
Dialogue: 0,0:01:34.82,0:01:41.00,Default,,0000,0000,0000,,I'm going to use my voltage difference and\Nmy resistance to find power.
Dialogue: 0,0:01:41.00,0:01:42.55,Default,,0000,0000,0000,,So let's see how we do that.
Dialogue: 0,0:01:46.08,0:01:46.86,Default,,0000,0000,0000,,Let's flip this over.
Dialogue: 0,0:01:48.51,0:01:53.50,Default,,0000,0000,0000,,Okay, now I know I one,\Ntwo, three, and IX.
Dialogue: 0,0:01:53.50,0:01:55.25,Default,,0000,0000,0000,,I also know my resistances.
Dialogue: 0,0:01:55.25,0:01:56.77,Default,,0000,0000,0000,,So the next thing I'm going to do.
Dialogue: 0,0:01:56.77,0:01:59.34,Default,,0000,0000,0000,,Remember I use my\NKirchoff's Law to get those.
Dialogue: 0,0:01:59.34,0:02:02.67,Default,,0000,0000,0000,,Now I'm going to use Ohm's Law to\Nfind the voltage difference, and
Dialogue: 0,0:02:02.67,0:02:05.79,Default,,0000,0000,0000,,the voltage difference\Nis going to be V3 here.
Dialogue: 0,0:02:05.79,0:02:09.72,Default,,0000,0000,0000,,So V3 is going to be I3 times R3.
Dialogue: 0,0:02:10.81,0:02:15.89,Default,,0000,0000,0000,,That's the same voltage difference\Nthat is across this current source, so
Dialogue: 0,0:02:15.89,0:02:22.73,Default,,0000,0000,0000,,if I had V current source, let's call\Nit VS2, that would be equal to V3.
Dialogue: 0,0:02:24.34,0:02:28.17,Default,,0000,0000,0000,,Now, I've used my Kirchoff's Law\Nto find my current.
Dialogue: 0,0:02:28.17,0:02:31.24,Default,,0000,0000,0000,,I've used my Ohm's Law to\Nfind my voltage difference.
Dialogue: 0,0:02:31.24,0:02:35.51,Default,,0000,0000,0000,,And now, I want to use my Power\Nequation in order to find the power.
Dialogue: 0,0:02:35.51,0:02:40.76,Default,,0000,0000,0000,,So, the power is equal to VS2 times Is,
Dialogue: 0,0:02:40.76,0:02:45.24,Default,,0000,0000,0000,,which is equal to I3R3 times Is.