j is for joule
james prescott joule helps adabot connect energy and work with force, distance, power and time.
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0:00Rise and shine, Adabot. It's time for work.
0:07Work? Work!
0:08Uh, okay.
0:43Who are you? And what are we working on?
0:47My name is James Prescott Joule. Perhaps you've heard of me.
0:51I think so. Aren't you a scientist?
0:54Exactly. And I've spent my entire life studying the way things work.
0:59What do you mean by work, exactly?
1:02I'm so happy you asked. Let's get working and I'll explain.
1:07Um, okay.
1:13Long ago, I defined work as force multiplied by distance.
1:18So, if we know how much force has been applied over a certain distance,
1:23then we can know how much work has been accomplished.
1:27Force multiplied by distance?
1:31Exactly!
1:31As I'm sure you know, it takes much more work to lift something up above your head
1:36than it does to raise it a few inches off the ground.
1:40And when we measure force multiplied by distance,
1:43we do so using a unit of measurement known as the joule.
1:48Wait, I thought you were named Joule.
1:50I am. I named the unit of measurement after myself.
1:54It is my life's work after all.
1:58That makes sense.
1:59Let me give you an example.
2:01Okay.
2:02To the table.
2:03To the table.
2:08Ooh, how about them apples?
2:10Indeed, Adabot.
2:12So it takes a force of about one newton to lift this apple.
2:16And if I lift this apple one meter, then I've done one joule of work.
2:21Okay, but what if you lifted 40 apples?
2:25Forty apples would be 40 joules of work!
2:29Whoa, that's a lot of work.
2:30Indeed.
2:31Indeed.
2:34So, if we light this 3 watt LED for 3 seconds, then we've done
2:409 joules of work.
2:423 watts times 3 seconds equals 9 joules.
2:47Now similarly, if we light this 60 watt incandescent bulb for 1
2:53hour, then we'll have done 216,000 joules of work.
2:59Whoa, that's a lot of joules.
3:01Exactly. So, if you really wanted to save power, you might consider using
3:06something like this, a 12-watt LED bulb.
3:10Oh, that would be a smart move.
3:13Indeed, Adabot.
3:14So, to calculate joules, we multiply force
3:20and distance, or power and time.
3:27Precisely, Adabot.
3:29So, are you ready to get to work?
3:32I think so.
3:33Good, because we're scheduled for 5,000 joules of work today.
3:38Wait, what?
3:39Come on, Adabot. Let's make hay while the sun is shining.
3:42Wait, there's hay now too?
3:44Oh, it's just an expression, Adabot. Come on!