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为什么火是热的? – 译学馆
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为什么火是热的?

Why Is Fire Hot?

[音乐]
[Music]
科学秀:儿童
SciShow kids!
最近这里的天气变得真的很冷
The weather has been getting pretty cold around here lately!
冬天快要来了
It’s almost winter,
地上已经有不少雪了
and there’s already lots of snow on the ground.
我们最喜欢在外面下雪又很冷时做的一件事是
One of the things we like to do when it’s cold and snowy outside
坐在沃斯堡的壁炉旁
is sitting around the Fort’s fireplace.
我们可以喝喝热巧克力 讲讲故事
We can drink hot chocolate, tell stories,
有时候我们甚至会烤烤棉花糖
and sometimes we even roast marshmallows.
真的是又惬意又暖和!
It’s so nice and warm!
但我们在火堆旁有几点需要特别注意
But we have some VERY important rules about being around fires,
对吧 吱吱?
don’t we, Squeaks?
[吱吱发出吱吱声]
[Squeaks squeaks]
我们知道任何火都不要靠得太近
We know to never get too close to any kind of fire,
也不要玩火柴或是炉灶
or play with matches or the stove.
我相信你们大部分人都知道这些规矩
I’m sure a lot of you know these rules too!
你们中的一些人还想知道更多
Some of you wanted to know more,
并问我们为什么火这么热
and asked us why fire is so hot.
这个问题问得真好!
That’s a really good question!
火非常热
Fire is very hot,
这就是我们不靠近它的原因之一
which is one of the reasons we don’t go near it.
而那个热量来自于它的能量
And that heat comes from energy.
你或许已经知道关于能量的一些知识
You might already know a little bit about energy.
能量使物体可以发生位移和变化
It’s the reason things move and change.
就如 当吱吱开始在堡垒里到处蹦蹦跳跳时
Like, when Squeaks starts bouncing all over the Fort,
我可能会说“他真的是精力十足!”
I like to say that he has a lot of energy!
我们从吃的食物中获得所需能量
We get the energy we need from the food we eat,
然后我们在做事时 如玩耍和成长的时候
and we use that energy to move and
使用那些能量来移动和发生身体上的变化
change when we do things like playing and growing.
我们移动时使用的是一种能量
The energy we use when we move is one type of energy.
热量是能量另一种形式
And heat is another type of energy.
这就是有时我们疯跑一会后会觉得很热的原因
That’s why we get so warm sometimes when we’re running around a lot!
在奔跑时 我们会消耗一些从食物中获得的能量
As we run, we use up some of the energy we got from our food
同时 我们体温也会升高一些
And we get warmer at the same time.
火跟那个差不多
Fire is kind of like that, too.
当某些东西着火时 就如木头在壁炉里燃烧时 它会发生改变
When something burns, like wood in a fireplace, it changes.
刚开始 它就是从树上砍下来的一块普通木头
It starts out looking like regular wood from a tree,
燃烧之后 它就变成黑乎乎的了
and then after it burns it becomes all black.
有时它还会变成小碎块 也就是我们说的木炭
Sometimes it also gets broken up into smaller pieces we call charcoal.
木头发生变化时 它耗尽了能量
As the wood changes, it uses up energy,
同时 它释放出热量
and at the same time, it gives off heat.
火产生热量的这个过程叫做“氧化”
The heat that comes from a fire happens because of something called combustion.
这个词涵盖范围很广
That’s a big word,
但它指的就是东西着火的时候发生了什么
but it just means what’s going on when something is burning.
东西燃烧需要达到三个条件
For something to burn, or combust, three things need to happen.
首先 要有可以烧的东西
First, there has to be something to burn,
就像壁炉中的木头
like the wood in the fireplace.
我们称燃烧的东西为燃料
We call the stuff that burns in a fire – fuel
其次 燃烧需要氧气
Second, there needs to be something called oxygen,
氧气是我们周围空气中的一部分
which is a part of the air that’s all around us.
[吱吱发出吱吱声]
[Squeaks squeaks]
吱吱你说得对
You’re right, Squeaks!
不只是火需要氧气
Fire isn’t the only thing that needs oxygen.
我们也需要氧气
We do, too!
我们每次呼吸都能将氧气带入到我们的身体中
We take oxygen into our bodies every time we take a breath of air.
第三 火需要的是……热量
The third thing that fire needs is actually… heat!
[吱吱发出吱吱声]
[Squeaks squeaks]
对 刚开始需要一点点热量 火才能烧起来
Yeah, fire needs a little bit of heat to get started.
如果你以前看到过大人
If you’ve ever watched a grown-up light a candle
点燃生日蛋糕上的蜡烛或是点燃篝火的话
on a birthday cake or start a campfire,
他们可能用到了火柴
they might have used a match.
火柴发出的热量让火燃烧起来
It’s the heat from the match that gets combustion,
于是火开始烧起来啦
and the fire, started!
接着燃料燃烧并发生变化
Then the fuel burns, and changes,
并释放比刚开始从小火柴那得到的多得多的热量
and gives off much, much more heat than it started with from that tiny match.
在燃烧时会消耗大量能量
It’s using up lots of energy as it burns,
能量的一部分以热量的形式表现出来
and some of that energy comes out as heat.
但当火中的燃料烧光时
But when the fuel in a fire is all burnt up,
就没有东西可发生变化也不会发出热量了
there’s nothing left to change and give off that heat.
所以 当我们壁炉的所有木材都烧光时
So, if all the wood burns up in our fireplace,
火就会熄灭
the fire will go out.
但火还在燃烧时 它是非常烫的
But while it’s burning, it’s very hot!
现在你知道为什么了:因为它在释放能量
And now you know why: it’s because it’s giving off energy.
[吱吱发出吱吱声]
[Squeaks squeaks]
吱吱说得没错!这太神奇了!
You’re right Squeaks! It is amazing!
现在我的热巧克力没了
Now, I’m out of hot chocolate,
所以我要去续杯咯
So, I’m gonna go fill it up,
待会我来壁炉旁找你
and I’ll meet you back by the fireplace!
欢迎收看我们的节目
Thanks for joining us!
如果你对周围世界发生的事情有什么疑问
Do you have questions about things that happen in the world around you?
你可以到网站上把问题发给我们
We have a website where you can send them to us!
找个大人帮你登录网址patreon.com/scishowkids去看下就知道了
Just ask a grown-up to help you go to patreon.com/scishowkids to check it out.
我们下期见 在沃斯堡等你哦!
And we’ll see you next time here at the Fort!
[音乐]
[Music]

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视频概述

给孩子们介绍火的燃烧

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收集自网络

翻译译者

XC8849

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视频来源

https://www.youtube.com/watch?v=_4NoW8BIocY

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