Laura: Hello and welcome to Lex Education, the brand new podcast from comedian, author, star of Live at the Apollo, Mock The Week, Hypothetical, and Roast Battle, Laura Lexx and her brother Ron.
Ron: Hello I'm Ron.
Laura: In our brand new podcast adventure, science fan Ron tries to teach me, comedy queen Laura, enough science to pass a triple GCSE with limited success. Each week, Ron and I will focus on one of the different science topics, alternating between biology, chemistry and physics. Each episode will feature one lesson and one quiz. However, the twist is that even though you will just hear a jingle between the lesson and the quiz, we will have lived a whole week in the real world.That way we really see what's stuck in my brain.
Ron: quite often for lunch, I just make my own mushy peas and have them with carrots.
Laura: Might leave that in as the start Of the podcast, to be honest. Hello, Ron. It's episode three.
Ron: It's a magic number.
Ron: It's physics.
Laura: Now, listen, we know that you're here for lovely, pure science content.
Laura: There is a smut warning.
Laura: On today's show, ron is going to tell us some facts about Bulgar Wheat.
Speaker C: And that joke is going to resurface.
Laura: So just listen.
Ron: I believe it was lentils.
Laura: I think it was Bulgo wheat ron.
Laura: I believe it was definitely Bulga Wheat, because now I can't look at Bulgar Wheat anymore.
Ron: Sound off in the comments about what smells more like carb.
Speaker C: Yeah.
Speaker C: Today we're going to hit up some physics.
Speaker C: We're going to have a look at a lady has to throw a ball.
Laura: We're going to find out what's going on.
Laura: Listen, we kind of need your help on physics, because, as you'll hear in the episode, we both well, I mainly think it's garbage.
Laura: So if you've got any fun ideas for how physics can be more interesting, maybe you're a physics teacher and you teach this to children.
Laura: Hey, let us know.
Laura: You can contact us on all the socials Instagram, TikTok, Twitter, Facebook, Lex education.
Laura: Find the one you like best and come and chat to us there.
Laura: Or you can email us at lexeducation@gmail.com.
Laura: We also want to do a massive shout out to Pod Spike.
Laura: If you heard the last two episodes, you've heard us mentioned them before.
Laura: If you didn't hear the last two episodes, how did you get here?
Laura: But welcome anyway.
Laura: We're not sad about it.
Laura: Pod Spike really helped us launch this podcast, especially with doing the fiddly things that neither of us are great at, like helping us choose a podcast distribution app and how to hook that up to all the other distribution apps.
Laura: That didn't mean much to us a couple of months ago.
Laura: We just wanted to talk to each other about science and really showed us how to get that into people's phones.
Speaker C: So if you have any ideas about.
Laura: Launching a podcast, but just think, I don't even know how to do most of that talk to Pod Spike, because they have been brilliant with us.
Laura: We cannot recommend them enough.
Ron: Agreed.
Speaker C: Ron, how are you this week?
Ron: I'm doing really well this week.
Ron: I finally nailed the working from home lunch.
Speaker C: Oh, what do you have?
Ron: A bulga wheat and lentil salad that I just make a massive bowl of at the beginning of the week and then just scoop some each day.
Ron: It's brilliant.
Speaker C: Sounds disgusting, but I'm pleased for you.
Ron: Oh, no, it's great.
Ron: Right.
Ron: Sort of equal parts bulgar wheat and green lentils and then as much fresh veg as you want in there.
Ron: A bit of tomato, passata, red wine vinegar, basil, and then a bit of salt and pepper.
Ron: Perfect.
Speaker C: All right.
Ron: The only problem is that I've been informed that the smell of cooking lentils smells horrifically.
Ron: Like c**.
Speaker C: Nice.
Ron: Buy a candle.
Speaker C: Well, I hate that information.
Speaker C: I hate it, Ron.
Speaker C: I really hate it.
Speaker C: Hey, last week's episode was good.
Speaker C: Today we're moving on to physics, which I feel like physics is the worst one because it's the least good one.
Ron: Yeah, physics is the shittest to be there.
Ron: It's also the mathiest one, so it's going to be the hardest to translate into a podcast format.
Speaker C: Let's get into it, shall we?
Speaker C: Ron, what are we covering in today's lesson?
Ron: We're going to be talking about the basics of energy, what that means, the different types of it and how they interplay.
Speaker C: Basically, I remember two things about energy, the word kinetic and potential.
Ron: Perfect.
Ron: Those are two of the big ones.
Speaker C: Yeah.
Speaker C: Brilliant.
Speaker C: I've remembered those.
Ron: Okay, so in the syllabus, it first tells us a little bit about the history of energy.
Ron: It says that the concept of energy emerged in the 19th century, which I flat out don't believe, but I imagine they mean kind of energy in the sense that we understand it now.
Ron: And apparently it was developed to explain the work output of steam engines and then generalised to understand other heat engines.
Ron: So kind of just capitalism driving everything towards more efficiency, really.
Speaker C: Woohoo.
Speaker C: We love capitalism and unions.
Ron: Yeah.
Ron: And then I feel like whoever writes the syllabus just thrown in a bit of their agenda, because then they say limits to the use of fossil fuels and global warming are critical problems for this century.
Ron: Physicists and engineers are working hard to identify ways to reduce our energy usage.
Ron: It's not mentioned again, but they just wanted to get it in there.
Speaker C: Brilliant.
Speaker C: It's good to know.
Speaker C: It's reassuring.
Speaker C: Maybe once I've learned this, I'll be able to help with the climate crisis.
Ron: Potentially, yes.
Ron: What else could you tell me about energy in general?
Speaker C: Let me see.
Speaker C: I know energy can't be destroyed.
Speaker C: It can only be transferred, like when something goes cold.
Speaker C: It's not that energy has been destroyed or died or anything, it's that it's either gone into other things or become wind or something like that.
Speaker C: I know that there's the different types of energy.
Speaker C: What I vaguely remember is like, potential energy is like if a ball is at the top of a hill or an elastic band is real stretched, it's got potential energy, like stored up in it.
Speaker C: Kinetic has something to do with movement, I think.
Ron: Yeah, so that's actually my next question.
Ron: I found nine different types of energy.
Ron: You've said two of them.
Ron: Could you hazard a guess at the other ones?
Speaker C: Seven more.
Speaker C: Oh, you'll be lucky.
Speaker C: Electrical?
Ron: Yes.
Speaker C: Okay, I assume like heat energy.
Ron: Absolutely.
Ron: What's the one that kind of goes hand in hand with heat?
Speaker C: Cold?
Ron: No.
Speaker C: Light?
Speaker C: Yes, light energy.
Ron: Okay.
Ron: The other three are a little bit more obscure.
Speaker C: Energy, like metabolism energy when you break something down and it gets you energy from your food.
Ron: Well, you've already named the type of energy that that is.
Ron: You're talking about us getting no one that you've already mentioned out of this list.
Ron: No, let me finish my sugar.
Ron: So you're talking about getting the energy out of the food.
Ron: Food is made of what?
Speaker C: Atoms?
Speaker C: Cells?
Ron: Molecules.
Speaker C: Molecules.
Speaker C: Rubbish.
Ron: Okay, if you're getting the energy from these molecules, what type of energy do you think is in those out of the ones that you've already mentioned?
Speaker C: Potential.
Ron: No, because you don't put your food up on the top of a hill and then nibble it down to the bottom.
Speaker C: Stored up energy.
Speaker C: What's the name for stored up energy?
Ron: So that's an example of chemical energy.
Speaker C: I didn't say chemical energy yet, though.
Ron: Oh, f***.
Ron: No, you said electrical.
Ron: My bad.
Ron: So that's chemical energy.
Ron: There are actually three more because I thought you'd already said that.
Ron: So think about podcasts, audio energy, sound energy.
Ron: Yeah, that's the thing.
Ron: Okay, okay, think about the last episode that we did.
Speaker C: Frustration and energy.
Ron: No, that's all heat.
Speaker C: Micro energy.
Speaker C: So we were talking about magnetic energy.
Ron: That is one not what I was alluding to a good job.
Speaker C: Okay, well, that's good.
Ron: So last week we were talking about atoms.
Speaker C: Yeah.
Speaker C: Atomic energy, split the atom or nuclear energy.
Ron: Yes, that's kind of what we call it.
Ron: Yes.
Ron: We've already had some good fun with trying to work out what type of energy is in food.
Ron: So it says students should be able to describe all the changes involved in the way energy is stored.
Ron: When a system changes for common situations, for example, an object getting projected upwards and stuff like that.
Ron: All right, so let's jump into the first one and we'll work through that.
Ron: An object getting projected upwards, let's say.
Speaker C: By projected do you mean thrown?
Ron: Yeah, so I was going to say so let's say a woman throws a ball.
Speaker C: Thanks for making it a woman, Ron.
Speaker C: That's really good.
Speaker C: If you okay, she's throwing a ball.
Ron: Right up in the air before she throws it.
Ron: Where is that energy?
Speaker C: In her arm in the form of muscles.
Ron: Yeah.
Ron: And what kind of energy do you think muscles use?
Speaker C: Let me have a look at my little list.
Speaker C: You'd hope it's not nuclear.
Speaker C: Could be chemical.
Speaker C: If she's on the russian Olympic team.
Speaker C: Probably not magical or electrical.
Speaker C: Unless she's a robot.
Speaker C: So heat is she has got heat in her body.
Speaker C: And it is hard to be energetic when you're cold.
Speaker C: She's probably not glowing, so I doubt it's light.
Speaker C: I mean, I do make noises when I throw stuff, like, helps me throw things further, but I feel like that's not science.
Speaker C: Potential feels very likely to me.
Speaker C: Like, when you flex a muscle and a muscle is poised, it's full of potential energy.
Speaker C: And kinetic is about moving.
Speaker C: So moving.
Speaker C: So potential energy.
Ron: Not quite.
Ron: So work it back a little bit.
Ron: Actually, we've talked about this in the first episode.
Ron: So obviously muscles yeah, they're like the pistons that will move her arm.
Ron: But how do they power themselves?
Ron: Where do humans in general get their energy from?
Speaker C: The sun.
Ron: All right, a step after that.
Speaker C: I hate silences where you're breathing in.
Ron: No, there was more frustration at myself because I kept on saying, Work it back, work it back.
Ron: And, like, you're technically f****** right.
Ron: Which is quite frustrating.
Ron: All right, so photons coming out the sun, then.
Ron: What do the photons all right, let's work it all the way back.
Ron: Okay.
Ron: Energy leaves the sun.
Speaker C: Yeah.
Ron: Vitamin D.
Ron: Back again.
Ron: Back again.
Speaker C: Back to the sun.
Ron: Energy leaves the sun, lands on a plant, let's say lands on some cabbage.
Ron: Okay.
Speaker C: Yeah.
Speaker C: And then Photosynthesis happens.
Ron: Yes.
Ron: The cabbage grows a humour.
Ron: Eric Clapton's cancelled.
Ron: Well, cancelled.
Ron: That's not saying about him.
Speaker C: I wasn't I was thinking about a cabbage.
Ron: Certainly not.
Ron: Although it does support your antivaxx agenda.
Ron: So human eats the cabbage.
Speaker C: Yeah.
Speaker C: Poor human.
Speaker C: And she's got to throw a ball.
Speaker C: She is having the worst day ever.
Speaker C: So I guess then, chemical yes.
Ron: Do you remember our old friend ATP from the first episode?
Speaker C: I do.
Speaker C: And with inflation, he's now known as 2050.
Ron: So ATP, we remember, is the energy currency of the cell.
Speaker C: Yes.
Ron: That is just chemical energy.
Ron: The energy is all held within that chemical.
Ron: And muscles go through, shed loads of it whenever they do anything.
Ron: That's why you burn so much energy when you're exercising and stuff.
Ron: Okay.
Ron: Using the muscles in her arm, she converts that chemical energy into kinetic energy.
Ron: Absolutely, yes.
Ron: So she is converting chemical energy into kinetic energy, which she is then passing into the ball, which she then throws upwards.
Speaker C: So there's now, like, a bit Abbas in the ball, kind of.
Ron: Yeah.
Ron: So, I mean, bonus points if you can think of maybe another two types of energy that might have been created while she was, like, through the action of moving her arm.
Ron: I mentioned one of them earlier, heat.
Speaker C: Because movement creates friction, which is heat.
Ron: Yeah, definitely heat energy.
Ron: So not just from friction, obviously.
Ron: A little bit from friction, but also just all of these ATP molecules, they're all releasing energy.
Ron: Not all of that is going to get captured and used by the muscle.
Ron: So some of it is just going to become heat and it will heat up the system.
Ron: Let's say that she's well quick at throwing a ball, so her arm cuts through the air really quickly.
Speaker C: Yeah.
Ron: Might make a noise.
Speaker C: Yeah, I was going to say that.
Speaker C: I was going to say it's a bit of sound energy.
Ron: Yeah, I think probably that's it.
Ron: So at the top of its peak of the throw, what energy does the ball have?
Speaker C: Potential.
Ron: Yeah.
Ron: So at the very top, we're talking about her throwing it directly up above her head.
Ron: So at the very top, the ball has converted all of its energy into potential energy.
Ron: Then what do you think happens?
Speaker C: Gravity.
Ron: Yeah.
Ron: Pulls it back down and energy changes.
Ron: What does the potential energy then do?
Speaker C: I guess it changes back into kinetic energy.
Ron: Exactly.
Speaker C: Yeah.
Speaker C: Because it's then going to punch the ground.
Ron: Yeah, exactly.
Ron: Excellent, segue.
Ron: So the next situation on the list is a moving object hitting an obstacle.
Speaker C: So there will be some kinetic energy shift, because the ground, like some things on the floor, will move when the ball hits it.
Speaker C: Like if a pebble bounces or something.
Speaker C: That's transfer of kinetic energy.
Ron: Yes, absolutely.
Speaker C: Might be heat energy.
Ron: I would imagine a small amount of heat would be produced.
Speaker C: Sound.
Speaker C: Definitely sound.
Speaker C: A ball bouncing makes a sound.
Speaker C: So quite a lot of sound energy.
Ron: Yes.
Speaker C: If it was like vibrations and sound, I guess, would be the two most notable.
Ron: Yeah.
Speaker C: And it bounces back up, so the ball keeps the energy but goes back the other way.
Ron: Yeah.
Ron: So if we're imagining a bouncy ball every time and I mean, we've all thrown bouncy balls.
Speaker C: We've all thrown bouncy balls.
Speaker C: Who are planning Earth?
Ron: We love throwing bouncy balls.
Ron: Every time it bounces, it doesn't go quite as high.
Ron: That is because each time it bounces and all the ways it's working through the air and whatnot, it is losing energy.
Speaker C: Yeah.
Speaker C: Careless little ball.
Speaker C: Are you shuffling around?
Speaker C: You're very noisy in there.
Ron: I was shuffling around.
Ron: Yeah.
Speaker C: You noisy little boy.
Speaker C: You are making too much sound energy.
Speaker C: Stop converting your bulga wheat into sound energy, please.
Ron: Hooray.
Ron: I feel like you're getting better at learning.
Speaker C: You know, maybe you just caught me on a good day.
Speaker C: Maybe this just makes sense, though, because this is actual stuff.
Speaker C: No offence, Ron, I know that you love it, but all that stuff about cells is so pointless.
Speaker C: It means absolutely nothing in real terms.
Speaker C: So at least this is like, yeah, I know what movement looks like where I've never even seen a plum pudding, let alone a proton.
Ron: You need to stop using our podcast to push your antivaxx agenda.
Speaker C: Stop telling people I'm anxiety.
Speaker C: I'm vaxed.
Speaker C: I couldn't be more vaxed fit another vaccine in this tweet little body.
Ron: If you say that these things don't matter, then it's just a logical conclusion.
Ron: And I feel like you've started this podcast like a frog and boiling water people, they'll start and they're like, oh, cool, I'm going to learn a bit of GCSE stuff, and then later on, you just get them with it.
Speaker C: Look, we can either do a science podcast that's cool and make no money, or I can slowly Joe Rogan this s*** and will be millionaires.
Speaker C: Which one do you want?
Ron: A bit of both, to be fair.
Ron: Some of a right, okay.
Ron: Next one is a vehicle slowing down.
Ron: Start from wherever you want.
Speaker C: Excuse me, what is the question?
Ron: You know this thing that we've been doing for the last 20 minutes?
Speaker C: Yes.
Ron: So energy transfers when a vehicle slows down.
Speaker C: You're right, I have got better at learning a vehicle is slowing down.
Speaker C: So you are changing kinetic energy into heat energy.
Speaker C: I guess it's heat and the sound, definitely.
Speaker C: Like, if you apply a brake, especially my car, man, it needs a service.
Ron: Yeah, the tires and the brakes and everything, they get very hot when a vehicle slows down.
Speaker C: Yeah.
Speaker C: All right, cool.
Ron: Easy one.
Ron: Okay, next one.
Ron: Bringing water to a boil in an electric kettle.
Speaker C: So we're going from electricity, and that is being turned into heat and sound.
Ron: And so let's not jump a step.
Ron: So the filament in the kettle is electricity is going through it.
Ron: That electrical energy is getting transformed into heat, and then the heat from the filament gets passed into the water, which then heats up.
Ron: Then what happens?
Speaker C: Well, the water starts moving, so it becomes kinetic energy, too.
Speaker C: And maybe chemical energy, because you get bubbles.
Ron: Not really.
Ron: The bubbles come from cavitation as the water turns into steam, which is just heat and kinetic energy.
Speaker C: That's not chemical.
Speaker C: Okay, so, yeah, I would say heat sounding kinetic.
Ron: Yeah.
Ron: Cool.
Speaker C: Okay.
Speaker C: Yeah, no, I feel like I've got that.
Speaker C: So where are we going next?
Ron: Okay, so now, because physics is the most math of the three sciences that we're looking at, we're going to learn how to calculate a couple of different energies.
Ron: Okay, sure.
Speaker C: Sounds real useful.
Speaker C: Let's do it.
Ron: Okay, so the first one your friend of mine, kinetic energy.
Speaker C: I like that one.
Ron: Yeah.
Ron: If kinetic energy is good, it's easy to understand.
Ron: Do you know what Si units are?
Speaker C: No.
Ron: So Si Units.
Ron: That stands for the International Standard Unit.
Ron: So basically, you know how America and the UK, we hang on to things like inches and miles and stuff like that?
Speaker C: White power.
Speaker C: All my jokes fall very flat, Ron.
Ron: But it's not a comedy podcast, it's educational.
Speaker C: Why am I here then?
Ron: To learn?
Ron: Because you f***** it the first time around.
Ron: Come on, man.
Ron: Yeah, and then most sensible places in the world have gone metric metres, kilogrammes and stuff.
Ron: Millilitres those beta males that use the decimal system for everything that there needs to be a unit.
Ron: There is kind of the metric of that, which is the Si unit system.
Ron: The Si unit for energy is joules rather than the ones that you see in other places.
Ron: It's like Calories.
Ron: Calories is just a different unit for energy.
Ron: A jewel is defined as a ruby.
Speaker C: Or a sapphire or a diamond or an emerald or a garnet or topaz aquamarine amethyst.
Ron: Someone watched too much of the shopping.
Speaker C: Channels in genuine lapis lazuli, measuring just over a centimetre.
Speaker C: An exact republica of those ones.
Ron: I can just remember watching that and just being horrified by their hands.
Ron: Yeah, something really off about someone's hands that are just too manicured.
Ron: It's equal to the work done by a force of one Newton acting through one metre.
Speaker C: What are you talking about, Ron?
Ron: So the cool thing about Si unit is they are all linked together, right?
Speaker C: You are bandying about the word cool here.
Ron: You're the one making a science podcast.
Ron: You approached me.
Ron: They're all linked together.
Ron: Do you know where the.
Speaker C: Answer is?
Speaker C: No, Ron, you know I don't know that.
Ron: Yes, but it can't just be a lecture because I'm sorely underqualified to give one.
Speaker C: Yeah, okay, then let me have a think.
Speaker C: The gramme.
Speaker C: Do you know, it slipped my memory as to where the gramme was invented.
Speaker C: I'm going to guess Sheffield.
Ron: I'm not sure, actually, but the point that I'm trying to make so a gramme, a centimetre and a millilitre are.
Speaker C: All based walk into a bar and the bar you guys are tiny.
Speaker C: Shut up.
Speaker C: We're actually standard.
Ron: No, so a millilitre, a gramme and a centimetre are all linked around water.
Ron: So one millilitre of water, if you put it into a cube, that cube would be a centimetre squared and that cube of water would weigh a gramme.
Speaker C: Okay.
Ron: Pretty cool, right?
Speaker C: A centimetre squared is quite big.
Speaker C: Do you mean a millimetre squared?
Ron: No, the unit for energy, joules, is one unit.
Speaker C: It should be called Jewels.
Speaker C: Jewels sounds like a mate.
Speaker C: You've got that's like really nice.
Speaker C: Like our jewels will help you out.
Ron: For me, it sounds like he's having a unit houtonati down on New York.
Ron: Yeah.
Ron: So the unit of energy is equal to one of the unit of force, which is a Newton, named after Sir Isaac Newton, acting through one of the standard unit of distance, which is a metre.
Speaker C: What, a unit and a Newton and a metre?
Speaker C: They're the same.
Ron: The standard unit for energy is a dual yes.
Ron: Which is equal to one Newton acting through one metre.
Speaker C: What is a Newton?
Ron: It's the standard unit of force.
Speaker C: What do you mean, the standard unit of force?
Ron: Because we're talking about the standard units.
Speaker C: Yeah, but how do you have a standard force?
Speaker C: What do you mean?
Ron: Because force is a measurable thing.
Speaker C: Sure.
Speaker C: What is it?
Ron: Yeah, like gravitational force.
Ron: We can measure that.
Ron: The pull of gravity.
Ron: Or like, if you leant on a door, you'd be applying a force to that door and we can measure that.
Speaker C: Okay.
Speaker C: One single measure of force is a Newton.
Ron: Yes, exactly.
Ron: So one Newton.
Ron: And then if you pushed something with one Newton's worth of force, one metre, that would be one joule of energy.
Ron: Yes.
Speaker C: Okay.
Ron: Because they're all interlinked.
Ron: Okay.
Ron: So the formula for working out the kinetic energy of something is you take half the mass and you multiply that by the speed squared.
Ron: Let's say we had a baby.
Ron: The baby weighs what do babies weigh?
Ron: Like £10 now in kilogrammes?
Ron: What?
Speaker C: Nobody measures babies in kilogrammes.
Speaker C: No one's ever measured a baby in a kilogramme.
Speaker C: And I'll die on this hill.
Speaker C: That is sick and wrong.
Speaker C: If you've had a baby and someone says, how much does it weigh?
Speaker C: And you tell me in kilogrammes, I'm staring at you with absolutely no idea how big your baby is or how broken your body is.
Speaker C: That is ridiculous.
Speaker C: Don't you have a baby?
Speaker C: If you want to measure something in kilogrammes, I hesitate.
Ron: I do hate to agree with you, but I do have no idea how much babies weigh in kilogrammes.
Speaker C: Well, mackey weighs 4.6 kilogrammes.
Ron: Yeah.
Ron: Let's do it with mackey.
Ron: Okay, so we take half of the.
Speaker C: Gas, so 2.3 kilogrammes.
Speaker C: Hang on, is weight the same as mass?
Ron: For our purposes, yes.
Speaker C: Okay, so what is creaking?
Speaker C: Is it your chair?
Speaker C: It's very noisy.
Speaker C: You're a noisy little boy.
Speaker C: Sit still.
Speaker C: Stop clenching your bum cheeks, ron, when he was little and we didn't have enough car seats, so it was the 90s, it was fine, but Ron just sat on one of our laps in the back and he would clench his bum cheeks on purpose to just be gross and have them dig into your thighs.
Speaker C: He was Horrid little boy and he still is.
Ron: Okay, no, that's not entirely true.
Ron: I'd clench my bum cheeks at first because I was a small child, flying about like I was in a washing machine, because I was just sat on someone's lap, not strapped into the seat.
Ron: So sometimes I clenched just to get a bit of purchase, try and grip a knee.
Ron: Then you guys started complaining about it a lot.
Ron: So then I did start clenching this.
Speaker C: One horrible little boy.
Speaker C: Okay, so 2.3 kilogrammes of mackey multiplied.
Ron: By the speed squads.
Ron: We need to do the speed in metres per second.
Speaker C: So I've got to drop her now.
Ron: What?
Speaker C: What are we doing?
Speaker C: How do we find out how far she's going?
Ron: We don't have to drop her.
Speaker C: Where is she moving?
Speaker C: Is she just running?
Ron: She can move however you want.
Ron: If you want to drop her off something, I think that's on you.
Speaker C: And I'm not doing it.
Speaker C: I don't care about those podcasts enough to throw my dog off something.
Speaker C: So just the speed that she's running at is fine.
Ron: Kinetic energy in any direction.
Ron: Yes.
Speaker C: All right, so how fast does she run?
Ron: Probably ten metres per second.
Speaker C: Okay.
Speaker C: And we got to square that.
Ron: Yes.
Speaker C: So ten square metres per second.
Ron: I can't see your face.
Ron: I don't know if you're joking, but I'm looking very sternly at my mind.
Speaker C: It'd be fun if you could suddenly run in 3D, though.
Speaker C: What do you mean?
Speaker C: Of course you can run in 3D.
Speaker C: No, you can only really run, like, linear.
Ron: What if you ran up a hill?
Speaker C: Still a line, isn't it?
Speaker C: Because you're not running along both axis at the same time.
Ron: If you ran wiggly up a hill, you're running in 3D.
Speaker C: No.
Speaker C: So ten metres per second squared.
Speaker C: What's the is that?
Speaker C: Ten by ten.
Speaker C: So is that 100 metres per second?
Ron: Yes, it is.
Speaker C: So two, three kilogrammes times 100 metres per second.
Ron: Just times 100 times 100?
Ron: Yes.
Speaker C: So 230 kilogrammes.
Ron: No, we're working out the energy.
Speaker C: 230 jewels.
Ron: Yes.
Ron: 230 housing down the park.
Speaker C: So that's how much energy Mackie burns.
Ron: No, that's how much energy she has.
Ron: So think about the ball.
Ron: That the very athletic woman through upwards.
Ron: The ball has that energy, and Mackie has that energy when she runs.
Speaker C: Okay, but she might have more.
Speaker C: She's just not using it.
Ron: She has loads of energy in her body.
Speaker C: Yeah.
Ron: That's the amount of kinetic energy she has at any one point.
Ron: And then if she runs up a hill, she'll then gain potential energy, which she could then use to roll back down the hill or something like that, and she'll be heating up.
Ron: So she'll have more heat energy in her.
Speaker C: Yeah.
Speaker C: So that's fine.
Speaker C: I can remember that.
Speaker C: That is a math thing.
Speaker C: But why?
Speaker C: What is that?
Speaker C: Just because we were like, hey, a jewel gotta be a thing.
Ron: It basically says that the speed of something has an exponential relationship with the amount of energy that it has, whereas the mass is just linear.
Ron: So if you take an object, no matter what, let's say there's a ten kilogramme ball and there's a 20 kilogramme ball, if they're both moving at the same speed, then the 20 kilogramme ball has twice the kinetic energy of the ten kilogramme ball.
Ron: However, if we have two balls of the same mass, but one is going at ten metres per second, but the other one is going at 20 metres per second, we know that the one that's going at 20 metres per second has four times the kinetic energy of the other one because the speed is squared.
Ron: Does that make sense?
Speaker C: Sure, let's say it does.
Ron: Okay.
Ron: Cool.
Speaker C: Stuff like this just bends my brain a bit, because I'm like, a jewel isn't really a thing, is it?
Speaker C: It's just a number we needed to give to something to make it easier for us to understand it.
Speaker C: It's not a real thing.
Speaker C: You can't count the jewels.
Ron: You absolutely could.
Speaker C: Well, you could cut something open and get the jewels out of them.
Ron: No, but we could transfer that energy into a different kind of energy.
Ron: You absolutely can count the jewels.
Ron: Let's say, for example, let's use Mackie again.
Ron: So Mackie's running.
Ron: We want to work out how many jewels are in her.
Ron: We know how much she weighs.
Ron: She weighs 4.6 kilogrammes.
Ron: We don't know upon looking at her exactly how quickly she's moving.
Ron: But we could work that out really easily with just a tape measure and a stop watch, so we can work out how quickly she runs.
Ron: And then using this very simple equation, we know how much kinetic energy she has when she moves.
Speaker C: Yeah, but it's not real.
Speaker C: They're not things.
Ron: But what if we discussed it in a more sort of consequential example?
Ron: So let's say let's talk about a car.
Ron: You and I were in a car accident together, only, what, like, eight months ago.
Ron: So if we can work out the kinetic energy of a car, we know how much energy is then going to be different.
Speaker C: Okay.
Ron: Crashes into something.
Ron: We know how strong we need to make seat belts and airbags, and we know how much we need to make the crumple zones crumple and that sort of thing.
Speaker C: Yeah.
Speaker C: All right.
Speaker C: Okay.
Speaker C: That makes sense.
Speaker C: I like that.
Speaker C: So should cars have different speed limits depending on how big they are?
Ron: No.
Speaker C: Where the little girls, like, if you hit me at 30, I might survive.
Speaker C: That's not necessarily true if you're driving a big car.
Ron: Yeah, that is true.
Ron: If we're actually talking about if we wanted to adjust policy, I don't think different speed limits is necessary.
Ron: Necessary.
Ron: But it's just if you're in a bigger car because you have more kinetic energy, obviously you need to leave a much bigger space in between you and the next car.
Speaker C: Yeah, all right.
Speaker C: Okay.
Speaker C: I like that.
Speaker C: Thank you for explaining it like that.
Speaker C: Now it feels less like, what's the point?
Ron: Okay.
Ron: The next one is going to feel a lot more what's the point?
Ron: Because the next one that we're going to discuss is elastic, potential energy.
Ron: So potential energy is one of your favourites.
Speaker C: Big fan.
Ron: We're going to learn how to calculate two different potential energies, elastic and gravitational.
Ron: So elastic, and then this is one of the things that I really like about physics, is how the same kind of patterns pop up.
Ron: So obviously, the equation we just learnt for kinetic energy, half times mass times speed squared, the equation for elastic potential is half times the spring constant.
Ron: Will come on to that in a second times the extension of the spring squared.
Ron: So you see, it's like the same pattern, but just with different the spring constant.
Ron: And I think this is why this is going to annoy you, and we might move on from elastic.
Ron: The spring constant literally just describes how hard it is to pull the spring.
Ron: Or the elastic band or something.
Speaker C: Okay.
Speaker C: So how much resistance is in the elastic?
Ron: Exactly?
Speaker C: Okay.
Ron: Yeah.
Speaker C: What do you measure that in?
Speaker C: Is that in Newton's?
Speaker C: Because it's force.
Ron: I was googling that before we so it's Hooke's lawton metres or Newton's per metre or Kilogrammes per second squared, apparently.
Speaker C: Newton's per metre.
Ron: Let's just go with Newton's per metre.
Ron: So how much force do you need to extend that spring?
Ron: A metre.
Speaker C: Yeah.
Speaker C: Okay.
Ron: And then we're going to multiply that by the extension squared times how far you stretched it.
Ron: Squared, exactly, yeah.
Speaker C: So is that in millimetres?
Ron: That metres is the si unit for distance.
Speaker C: Okay.
Ron: So if we were going to talk about maybe a bungee jumper, so I have not a scooby do on what the spring constant of a bungee would be, but let's say it's 100 Newtons per metre, and then if it extends by 50 metres, so that's 2500 when it's squared.
Ron: So we times that by 100, half it.
Ron: And then that would be the elastic potential of the bungee cord.
Speaker C: And we'd want to know that because we want to know how far back up the spring is going to ping.
Speaker C: So we don't smash into a bridge.
Ron: Exactly.
Ron: Yeah.
Ron: Or even say it had two looser spring constant.
Ron: We don't want the person to just keep on stretching the bungee and just hit the floor.
Speaker C: Yeah.
Speaker C: Okay.
Speaker C: All right.
Speaker C: I like things much more when they have a use.
Ron: Yeah.
Ron: I'm not just mackie dicking around.
Ron: That makes sense.
Speaker C: It makes sense now.
Speaker C: I'm like, oh, I shouldn't let her run too fast if she's heading for a wall.
Ron: Exactly.
Ron: We should slow our dogs down.
Ron: So then the last one is gravitational potential energy.
Ron: And this one's, the easiest one, basically how heavy the thing that you've got is how high up you've put it and how strong the gravitational field is.
Speaker C: Height, gravity.
Ron: Yeah.
Ron: And you just multiply the three of those together.
Ron: So mass times height times gravitational field strength.
Ron: So, off the top of my head, I think the gravitational field strength field strength is 9.85 or something for the Earth.
Speaker C: Yeah, that's what I thought.
Ron: Practical uses for this would be.
Ron: When is gravitational.
Speaker C: Is this like when they say if you drop a penny off the Empire State Building, it could kill someone?
Ron: Yes.
Ron: When people lie about that, they are referring to things like this, because a.
Speaker C: Penny isn't much, because it's very light, but it's coming from a big height, so that changes the energy it's got in it.
Ron: Yeah, exactly.
Ron: So if you took it up the Empire State Building she took it up the Empire State.
Speaker C: Mate, it smells like lentils in here.
Ron: Yeah.
Ron: I'm pretty sure Mythbusters disproved that, but maybe love Mythbusters.
Ron: Who didn't use the mythbusters.
Speaker C: I assume a lot of people.
Speaker C: Otherwise it would still be on Turley.
Speaker C: But you loved it, didn't you?
Ron: Mythbusters was great, although it was one of the sad.
Ron: One of the things that I hate learning about is when people that you sort of see on screen and stuff aren't as good mates as you think.
Ron: So the two guys from Mythbusters f****** despise each other.
Speaker C: Oh, really?
Ron: Yeah.
Ron: And, you know, like, flight the Concord, they don't get on.
Speaker C: No, I knew that.
Speaker C: Yeah.
Speaker C: Wait till people find out we're not brother and sister.
Ron: Yeah, well, we are, but we just hate each other.
Speaker C: We hate each other.
Ron: Just doing it for the sweet podcast money.
Ron: Yeah.
Ron: Mythbusters disproved it, but what I imagine the person that first put that about might have been saying is that the energy in a penny when you take it up to the top of the Empire State Building is enough to kill a person.
Ron: Yeah.
Ron: And then that's the three that they want you to learn, basically.
Speaker C: Yeah.
Speaker C: All right.
Speaker C: And I definitely know those now forever.
Ron: Yeah.
Ron: I think the most interesting part of that is the way that the equations sort of interplay with each other and the stuff about the units, because I.
Speaker C: Like the bit with the dog.
Ron: Right, yeah.
Ron: That's the end of today's class.
Ron: I'll see you next week for the quiz then.
Speaker C: All right.
Speaker C: I will be revising constantly.
Speaker D: It is one week later here in the land of the world.
Speaker D: Although for listening, it's like magic.
Speaker D: It's just happening.
Speaker D: There's a tiny sting and then you'll hear time travel.
Speaker D: Ron, you're going to test me now on energy?
Ron: Yes.
Ron: There should be a fun one.
Speaker D: Okay, how many questions are we talking?
Ron: We're only doing three questions, but there are 123-4567, 815 points available, 14 points.
Speaker D: Available, 14 points total across three questions.
Speaker D: Okay, here we go.
Speaker D: Number one.
Ron: Wait.
Ron: No, I can't count.
Ron: 17 points total.
Speaker D: Oh, Lord, I didn't stand a chance.
Ron: Okay, what are the different types of energy?
Speaker D: Okay, we've got electrical bing, magnetic bing, nuclear bing, kinetic bing, potential bing, chemical.
Ron: Bing, three more light bing, sound bing.
Speaker D: One more gravitational.
Ron: Gravitational is part of potential dang.
Speaker D: All right, what is the 9th one?
Ron: Heat.
Speaker C: Heat, yeah.
Speaker D: Okay.
Speaker D: One of the biggies eight out of nine.
Speaker D: I'm happy with that.
Ron: No, bloody good.
Ron: D*** good work.
Speaker D: That was d*** good work.
Speaker D: Thank you.
Ron: Okay, what is the unit of energy?
Ron: Yes.
Ron: A jewel.
Ron: Just like mom's jumpers.
Ron: Okay, right.
Ron: The next one is a bit more tick the box, get the right answer kind of question.
Ron: What are the energy changes of someone pulling back a bow and firing an arrow into a target?
Speaker D: Okay, so first of all, you are transferring chemical light like heat energy into a muscle moving, which is kinetic energy, and you're pulling the arrow and the bow, so that's kinetic energy.
Speaker D: Then there's potential energy stored in the bow.
Speaker D: And then when you let go, you turn that into kinetic energy and sound energy and probably some heat energy at the friction as it goes through the air.
Speaker D: I suppose the arrow has potential energy while it's flying, too.
Speaker D: And then when the arrow sunks into something, it makes sound energy and vibrations go through the Earth and split the Earth.
Speaker D: So kinetic.
Ron: Yes.
Ron: Good.
Ron: Very close.
Ron: I counted 123-4567 points for that.
Speaker C: So I got 17.
Ron: Yeah, I think it was actually out of 18.
Speaker C: So there were nine points available if.
Speaker D: You got the nine types of energy, one point for jewels, and then how many points were available for question?
Ron: 312-34-5678.
Speaker D: So it's 18 total.
Speaker D: So I only missed out two pole points.
Ron: You missed out heat energy and you.
Speaker D: Missed out heat energy at the beginning.
Ron: Yes, at the beginning.
Ron: And then you missed out heat when the arrow hits the target.
Ron: The only wrong thing, I think you said there was well, you said the arrow has potential energy, which technically it does when it's flying through the air, because it's not on the ground.
Ron: But that was not transferred into it in the act of firing it, assuming you fired it flat, if you see what I mean, because it already had it when it was in the boat.
Speaker D: What if I picked it up off the floor to fire it then?
Ron: That's not the question.
Speaker C: All right, well, I'm happy with that.
Speaker D: That's fine by me.
Speaker D: Let us know what you scored.
Speaker D: We're on Twitter and Instagram at Lex Education.
Speaker D: And if you want to question any of Ron's Teeth teaching methods or facts, email us at lexeducation@gmail.com.
Speaker D: Thank you so much for listening.
Speaker D: We'll be back next week when we are back to Biology G Oo, which is Ron's favourite.
Speaker D: Look at his little monkey face lighting up.
Speaker D: Always a cutie.
Speaker C: Thanks for listening.
Speaker C: We'll see you next week.
Speaker C: Goodbye.
Ron: Class dismissed.
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