评论
打印
The weather has been getting pretty cold around here lately!
这附近的天气最近变得相当冷了!
It's almost winter, and there's already lots of snow on the ground.
快到冬天了，地上已经下了很多雪。
One of the things we like to do when it's cold and snowy outside is sit around the Fort's fireplace.
当外面又冷又下雪的时候，我们喜欢做的一件事就是坐在城堡的壁炉旁。
We can drink hot chocolate, tell stories, and sometimes we even roast marshmallows.
我们可以喝热巧克力，讲故事，有时我们甚至烤棉花糖。
It's so nice and warm!
如此美好又温暖！
But we have some /very/ important rules about being around fires, don't we, Squeaks?
但是我们有一些/非常/重要的关于在火附近的规则，不是吗，吱吱?
We know to never get too close to any kind of fire, or play with matches or the stove.
我们知道永远不要太靠近火，也不要玩火柴或火炉。
I'm sure a lot of you know these rules too!
我相信你们很多人也知道这些规则!
Some of you wanted to know more, and asked us why fire is so hot.
有些人想了解更多，问我们为什么火这么热。
That's a really good question!
这真是个好问题！
Fire is very hot, which is one of the reasons we don't go near it.
火很热，这是我们不靠近它的原因之一。
And that heat comes from energy.
热量来自能量。
You might already know a little bit about energy.
你可能已经对能量有所了解了。
It's the reason things move and change.
这就是事物移动和变化的原因。
Like, when Squeaks starts bouncing all over the Fort, I like to say that he has a lot of energy!
就像，当吱吱开始在堡垒里跳来跳去的时候，它有很多能量!
We get the energy we need from the food we eat, and we use that energy to move and change when we do things like playing and growing.
我们从我们吃的食物中获取我们需要的能量，当我们做像玩耍和成长这样的事情时，我们用这些能量来移动和改变。
The energy we use when we move is one type of energy.
我们移动时使用的能量是一种能量。
And heat is a type of energy, too.
热量也是一种能量。
That's why we get so warm sometimes when we're running around a lot!
这就是为什么当我们经常到处跑的时候，我们有时会感到很温暖!
As we run, we use up some of the energy we got from our food, and we get warmer at the same time.
当我们跑步时，我们消耗了从食物中获得的一些能量，同时我们也变暖了。
Fire is kind of like that, too.
火也是如此。
When something burns, like wood in a fireplace, it changes.
当某些东西燃烧时，比如壁炉里的木头，它会发生变化。
It starts out looking like regular wood from a tree, and then after it burns it becomes all black.
它一开始看起来像普通的木头，然后燃烧后变成黑色。
Sometimes it also gets broken up into smaller pieces we call charcoal.
有时它也被分解成小块，我们称之为木炭。
As the wood changes, it uses up energy, and at the same time, it gives off heat.
随着木材的变化，它消耗能量，同时，它散发热量。
The heat that comes from a fire happens because of something called combustion.
火产生的热量是由燃烧产生的。
That's a big word, but it just means what's going on when something is burning.
这是一个很重要的词，但它只是指某物燃烧时发生的事情。
For something to burn, or combust, three things need to happen.
某物要燃烧或燃烧，需要三个条件。
First, there has to be something to burn, like the wood in the fireplace.
首先，必须有东西可以燃烧，比如壁炉里的木头。
We call the stuff that burns in a fire fuel.
我们把在火中燃烧的东西称为燃料。
Second, there needs to be something called oxygen, which is a part of the air that's all around us.
其次，需要一种叫做氧气的东西，它是我们周围空气的一部分。
You're right, Squeaks!
你说得对，吱吱！
Fire isn't the only thing that needs oxygen.
火不是唯一需要氧气的东西。
We do, too!
我们也需要！
We take oxygen into our bodies every time we take a breath of air.
我们每次呼吸空气时都把氧气吸入体内。
The third thing that fire needs is actually … heat!
火所需要的第三件东西实际上是…热量！
Yeah, fire needs a little bit of heat to get started.
是的，火需要一点热才能开始燃烧。
If you've ever watched a grown-up light a candle on a birthday cake or start a campfire, they might have used a match.
如果你曾经看到一个成年人点生日蛋糕上的蜡烛或生篝火，他们可能会用火柴。
It's the heat from the match that gets combustion, and the fire, started!
火柴的热量使它燃烧起来，火就开始燃烧了!
Then the fuel burns, and changes, and gives off much, much more heat than it started with from that tiny match.
然后燃料燃烧，发生变化，释放出比开始时多得多的热量。
It's using up lots of energy as it burns, and some of that energy comes out as heat.
它在燃烧的过程中消耗了大量的能量，其中一些能量以热的形式释放出来。
But when the fuel in a fire is all burned up, there's nothing left to change and give off heat.
但是当火中的燃料全部燃烧殆尽时，就没有什么可以改变和散发热量了。
So, if all the wood burns up in our fireplace, the fire will go out.
所以，如果我们壁炉里的木头全部烧完，火就会熄灭。
But while it's burning, it's very hot!
但是当它燃烧的时候，它是非常热的!
And now you know why: it's because it's giving off energy.
现在你知道为什么了：因为它在释放能量。
You're right Squeaks!
你说对了，吱吱！
It is amazing!
很神奇吧！
Now, I'm out of hot chocolate, so I'm gonna go fill it up, and I'll meet you back by the fireplace!
现在，我的热巧克力用完了，所以我要去把它加满，然后在壁炉边等你!
Thanks for joining us!
谢谢收看!
Do you have questions about things that happen in the world around you?
你对周围发生的事情有什么疑问吗?
We have a website where you can send them to us!
我们有一个网站，你可以把疑问发给我们！
Just ask a grown-up to help you go to patreon.com/scishowkids to check it out.
让一个成年人帮你登陆patreon.com或scishowkids看看。
And we'll see you next time here at the Fort!
我们下次在堡垒见！
