评论
打印
Squeaks and I are exploring! We're looking for insects!
我和吱吱正在考察，我们在找昆虫！
We know that some insects make their homes under rocks.
我们知道有些昆虫在石头下安家。
So we're trying to turn over a couple of these rocks to see what we can find!
所以要把这些石头翻过来，看看能找到什么！
But they're really big and heavy, and we can't get either of them turned over.
但它们又大又重，我们一块也翻不过来。
There has to be something we can do.
我们总会有办法的。
Great idea, Squeaks! A few weeks ago, we used a tool called a ramp to help us do work.
吱吱，好主意。几周前，我们曾用斜坡帮我们工作。
A ramp, which looks a lot like a slide, is one kind of simple machine.
斜坡看起来很像滑梯，是一种简单的器械。
Like all machines, a simple machine is just something that makes work easier.
和所有的器械一样，简单的器械能让工作变简单。
That ramp sure helped us move those books into the house!
那个斜坡确实能帮我们把书搬到房子里！
And there's another simple machine that we can use to help us turn over those rocks!
还有另一种简单的器械能帮我们把石头翻过来！
This one is called a lever.
它叫做杠杆。
A lever basically looks like this: a long bar that's balanced on something underneath.
杠杆基本上是这样的：一个长条在底下的某物上平衡。
And that something is called a fulcrum.
那个某物叫做支点。
By pushing down on one end of the lever, the fulcrum makes the other end go up.
通过向下推杠杆的一端，支点会使另一端升起来。
Just like a see-saw at the playground!
它就像游乐场里的跷跷板！
It's just a long bar, that's balanced on a fulcrum.
它就是一个在支点上平衡的长条。
Levers make work easier, by helping us lift things that would be too heavy to lift on our own.
杠杆让工作变得简单。因物体太重，我们自己提不起来，但杠杆能帮我们抬起它来。
If Squeaks hops on the low end of t自己he seesaw,
如果吱吱在跷跷板的低端，
and I push down on the high end, the lever moves on the fulcrum, and I can lift Squeaks up.
我从高端往下压，杠杆在支点上运动，我就能把吱吱抬起来。
It's a lot easier for me to lift Squeaks this way than if I tried to just pick him up.
我用这种方法抬吱吱比直接拿起它简单多了。
Our simple machine made my job easier!
简单的器械让工作变得容易！
So let's use a lever to see if it can help us lift up these rocks!
那么就让我们看看能否用杠杆帮我们抬起这些石头吧！
Alright, we'll put one end of the lever under the edge of this first rock.
我们把杠杆一端放在第一块石头边的底部。
Next, we'll use this smaller rock as our fulcrum, and put it under the middle of the lever.
接下来，我们用这块小石头做支点，把它放在杠杆中间的位置。
Now we can push on the high end of the lever and the rock goes up!
现在，我们从杠杆的高端压下去，石头起来了！
Look we did it! But it was still kind of hard.
看，我们做到了！但仍有点儿费劲。
I wonder if there's something we can do to make the job even easier?
我想知道还有其他办法能让工作更简单吗？
Let's try something a little different for the second rock.
我们在抬第二块石头时做些改变。
This time, we'll put the fulcrum closer to the rock we want to lift.
这次，我们把支点靠近想要抬起的石头。
Let's set up our lever, give the high end a good push down, and...Bingo!
放置好杠杆，从高端往下压，成功了！
That was a lot easier.
这次简单多了。
For levers like this one, the closer the fulcrum is to the thing you want to lift, the easier it is to lift it!
对于这样的杠杆来说，支点越靠近你想要抬起的东西，就越容易抬起它！
And that's what makes a lever a kind of simple machine!
这使得杠杆成为一种简单的器械!
Even though it's super-simple, a lever helps us do work!
杠杆虽然很简单，但能帮我们工作！
Levers are everywhere, and they sometimes don't look much like a see-saw,
杠杆无处不在，它们有时不太像跷跷板，
or even like the lever we used to lift our rocks.
甚至不像我们用于抬石头的杠杆。
For example, did you know that when you use a wheelbarrow to carry something,
例如，你知道用手推车搬运东西时，
you're using a kind of a lever?
你在用一种杠杆吗？
It's true! The wheel of the wheelbarrow acts as the fulcrum,
这是真的!手推车的轮子充当支点，
and instead of pushing down on the handles, you pull them up to lift what's inside!
你不是往下推把手，而是把它们拉起来，从而抬起里面的东西！
We use levers to open bottles, too, and to dig in our gardens, and even to eat our food!
我们也用杠杆开瓶子，挖花园，甚至是吃东西！
We'll be back soon with more simple machines, but in the meantime, Squeaks and I have some insects to find!
我们很快就带着更多简单的器械回来，但与此同时，我和吱吱还有一些昆虫要找！
Thanks for joining us on SciShow Kids!
感谢您收看本期的儿童科学秀！
Do you have a question about machines, or insects, or anything else at all?
你对器械、昆虫或其他任何东西有什么疑问吗？
Ask a grownup for help, and leave us a comment down below, or send us an email to kids@theSciShow.com!
找个大人帮忙在下方留言或发邮件至kids@theSciShow.com！
And we'll see you next time!
我们下期见！
