o is for ohm
a campfire song introduces ohm’s law and the relationship between voltage, current and resistance.
1080p web copy from the archived upload. the source file is preserved.
automatic captions, checked for structure and key terms; corrections welcome.
read the transcript
automatic captions, checked for structure and key terms; corrections welcome.
0:01[unclear opening audio]
0:29And some say you can still hear the blue smoke monster
0:35howling in the night.
0:38Ooh! Spooky story.
0:41Very spooky, Mho. Thank you for sharing it.
0:45Hey, how about we lighten the mood a little bit with some music?
0:50I brought my guitar here.
0:51Well, I've been working on a little song.
0:54Have either of you heard of the scientist Georg Simon Ohm?
0:58I haven't.
0:59No.
1:00Fantastic.
1:02Adabot, throw me a G chord, please.
1:04Will do.
1:09Yeah.
1:12Georg Simon Ohm was experimenting,
1:15and he happened upon something very interesting.
1:18He found that volts and currents are related to each other, but it's not like
1:23they're cousins or sisters or brothers.
1:26It's a rule that we now call Ohm's Law.
1:31You can't break Ohm's Law because it's always true.
1:39To find one value, you only need the other two.
1:46Say you're working in a circuit and you need a certain current
1:5010 milliamps from a 9-volt supply
1:53How many ohms will give you those amps?
1:57You don't have to guess or take any chances
2:00Just apply and rely on Ohm's law
2:05You can't break Ohm's law
2:09Because it's always true
2:13Find one value, you only need the other two
2:21Divide voltage by current to find the resistance
2:28Resistance times current will tell you the volts
2:34Divide voltage by resistance to find the current
2:40Nice.
2:41And that's all that we call Ohm's Law.
2:45Wow.
2:47So, you really can't break Ohm's Law?
2:51No, you can't.
2:52Like, not even sometimes?
2:53It is always true.
2:55And to find one of the values, I just need the other two.
2:58You've got it!
3:01You can't break Ohm's Law, because it's always true.
3:08To find one value, you only need the other two.
3:47We'll see you next time.