Name: 温度についての誤解 (Misconceptions About Temperature)
Uploaded: 2021-01-14T04:58:23.000Z
Duration: 4 min
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

When you touch an object and it feels warm or cold, what is that really telling you about

現在進行形

the object? Here, I have a metal hard drive and a book and I'm going to ask people to

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compare their temperatures. Which one do you think will feel warmer - the book or the hard

Yeah, tell me if one is hotter or colder or if they're the same temperature. How do they

I'd say the hard drive is a lot colder than the book. 'Cause the book's got more knowledge.

Metal's normally a little bit chillier if you leave it in a colder temperature.

What if I said they're both the same temperature? What would you say?

Well, maybe the way I can prove it is I have an infrared thermometer. What do you think

I think science might be able to answer that. And I'm not a scientist!

Let's measure the temperature of the book. What do you see?

I'm trying to figure it out, actually. Trying to figure out why'd they be the same temperature.

They don't feel the same temperature, though.

So, why does that feel colder if they're the same?

I'm not a scientist! Come on, you tell me.

I'll try to answer that question with another little experiment. Here is an aluminium block.

And a plastic block. How do their temperatures compare?

Let's take this to the next level. I'll put an ice cube on both plates. What will we see?

I'm guessing it would stay solid on this one and melt on this one.

So it's going to melt on the plastic but stay solid on the aluminium?

That one will melt more quickly than on the aluminium.

We put an ice cube on each of those. What do you see?

This is melting quicker than that one, even though this is aluminium and that's plastic.

Could aluminium be bad for the environment?

How would aluminium be bad for the environment?

It's about thermoconductivity - the rate at which heat is transferred from one object

to another. So when you felt these blocks originally, I know this one felt a lot colder.

But you know from the other example we did, that they must both be the same temperature.

They've both been outside for a while. We see the aluminium block is melting the ice

faster than the plastic block because it's conducting the heat to the ice cube faster.

With the plastic block, it's a worse thermoconductor. So, heat is being transferred less quickly

to this ice block and so it's staying iced.

In our first example, the hard drive felt colder, even though it was at the same temperature

as the book. That's because the aluminium conducts heat away from your hand faster than

the book conducts heat away from your hand.

Which makes the hard drive feel colder and the book feel warmer. So when you touch something,

you don't actually feel temperature. You feel the rate at which heat is conducted, either

towards or away from you. Think about this next time you hop out of the shower in winter.

It's much nicer to stand on the bath mat than on a towel beside it. Not because the bath

mat is warmer but because it conducts heat less quickly away from you.