99 Things Move-High

Things Move Written by Rhonda Lucas Donald

朗达·卢卡斯·唐纳德著

Introduction All around you, things move in many ways. Cars roll, birds fly, balls bounce, and children run. Some things seem to move on their own, while other things have to be moved. Some things move quickly, and some things move slowly. Some things move in a straight line, and others move in a circle. Many things change direction as they move.

在你周围，事物以多种方式移动。 汽车滚动，鸟儿飞翔，球弹跳，孩子们奔跑。 有些东西似乎是自己移动的，而有些东西却必须被移动。 有些东西走得快，有些东西走得慢。 有些东西是直线运动的，有些东西是圆运动的。 许多事物在移动时改变方向。

You can see that things move in many different ways. Let's learn why things move. Let's also learn what makes them move in different ways.

你可以看到事物以许多不同的方式移动。 让我们来学习物体为什么会移动。 让我们也来了解一下是什么让它们以不同的方式移动。

At Rest or in Motion? Look at the two pictures. How are the cars in one picture different from the cars in the other picture? The cars sitting in the parking lot are at rest. The cars on the road are in motion. What makes some cars move while others stay at rest?

静止还是运动?看这两幅图。 一幅图中的车和另一幅图中的车有什么不同? 停在停车场里的汽车都在休息。 路上的汽车在运动。 是什么让一些汽车移动而另一些汽车静止不动?

Objects can't move on their own. They stay at rest until a force moves them. That force can come from a living or a nonliving thing. The sled above moves when the child pulls on it. The child could also get behind the sled and push it. Pushing and pulling are two kinds of forces.

物体不能自己移动。 它们静止不动，直到有力量推动它们。 这种力可以来自生物，也可以来自无生命的东西。 当孩子拉上面的雪橇时，它就会移动。 孩子还可以站在雪橇后面推它。 推和拉是两种力。

Before you can kick a ball to make it move, you need energy. You get energy from the food you eat. Making a force requires energy. It also takes a force to make a car move. So a car needs energy, too. But the person driving it does not have to push the car. The car has a motor that gets energy from the gas it burns. The motor uses this energy to make a force that turns the wheels. Then the car moves.

在你踢球让球移动之前，你需要能量。 你从你吃的食物中获取能量。 产生一个力需要能量。 让汽车移动也需要一个力。 所以汽车也需要能量。 但是开车的人不需要推车。 汽车有一个从燃烧的汽油中获取能量的马达。 马达利用这种能量产生推动车轮转动的力。 然后汽车开动了。