Question

    Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren’t very smooth rub together to make heat energy. The faster you rub two things together, the more friction ( and heat) you can make. Let’s discover friction!

WHAT YOU’LL NEED:·Soap ·Water· Your hands!

WHAT TO DO:

1. Make sure your hands are dirty.

2. Rub your hands together until you feel the heat of your hands.

3. Now, use soap and water to get your hands very slippery(滑的).

4. Try to make friction happen while your hands are slippery.

5. Please write down what has happened.

LET’S TALK!

Friction is an energy that happens when two things rub together. When friction happens, it makes heat! When your hands are slippery, they won’t make very much friction and your hands won’t get so hot.

DID YOU KNOW?

(1)Friction happens when you stop your fast running bike.

(2)Ancient people made fires by rubbing two pieces of wood together. Friction happened though they didn’t know it.

________?_________

Friction is everywhere. Have you ever noticed situations where friction is happening? If not, ask your parents to take you out in a car. If it is not hot, touch the tires(轮胎) of the car before and after a short drive to see how much warmer they get from friction.

1.This passage is most probably ____________.

A.a science report B.a car advertisement

C.a rubbing introduction D.a chemistry program

2.____________ is not an example of friction.

A.Bike riding B.Car driving C.Hands rubbing D.Friction discovering

3.What’s the last column(栏目)?

A.THINK IT OVER! B.WHAT HAPPENED?

C.EVERYDAY ACTION: D.WORK WITH PARENTS

Answer

1.A

2.D

3.D

【解析】

这是一篇说明文，本文主要介绍有关摩擦的一些知识。摩擦是无处不在的。只不过看你是否注意到了它。

1.

推理判断题。根据“Let's discover friction!”可知，我们要探索摩擦，由此推断本文可能是一篇科学报道，故选A。

2.

推理判断题。根据“When your hands are slippery, they won't make very much friction and your hands won't get so hot.”可知摩擦手会产生摩擦力；根据“Friction happens when you stop your fast running bike.”可知骑自行车会产生摩擦力；根据“If it is not hot, touch the tires of the car before and after a short drive to see how much warmer they get from friction.”可知开汽车会产生摩擦力。摩擦的发现是不会产生摩擦力的，D选项不是例子。故选D。

3.

推理判断题。根据“If not, ask your parents to take you out in a car”, 可推知最后一个栏目是和父母合作，故选D。