问题 填空题

人站在湖边,可以看到水中的“鱼”,也可以看到水中的“蓝天”和“白云”.水中的“鱼”是属于光的______而形成的______像;“蓝天”和“白云”是由于光的______而形成的______像.

答案

(1)因为鱼儿是在水中的实际物体,是由于光线从水中通过空气折射进入了人的眼睛,我们看到水中的鱼,看到的是鱼的虚像,是由光的折射形成的.由于折射角大于入射角,所以鱼的实际位置要比看到的位置要深.

(2)水中的“蓝天”和“白云”是在水中形成的像,即平面镜成像,故看到水中的“蓝天”和“白云”是由光的反射形成的与物体等大的虚像.

故答案为:折射;虚;反射;虚.

阅读理解

阅读理解。

      Peter works in a food shop. He helps the shopkeeper (店主). He puts food on the shelves (架子) every day.

Then people come into the shop and buy the food. Today there aren't any bags of rice on the shelf. "Peter," says

the shopkeeper. "We need some bags of rice. Bring some rice to the shelf. Hurry up!"

      Peter runs to get some bags of rice. They're in another room and they are on the top of the shelf. The shelf

is high up (高). Peter is tall, but he can't reach (够到) the bags. He brings two boxes and puts one box on top of

the other. Then he stands on them. Now he can reach the bags on the shelf.

      The shopkeeper is coming. He is calling Peter.

      "Peter! Hurry up! What are you doing? Where are the bags of rice?" he says, he opens the door. He can't see Peter on the boxes.

      "Don't open the door!" Peter says. Then Peter falls down (跌倒)!

      Now Peter is on the floor. There is some rice on his head.

1. Peter helps the shopkeeper _______. [ ]

A. sell food sometimes

B. carry bags of oranges

C. in a food shop

D. buy some rice today

2. People come to the shop for _______. [ ]

A. the vegetables

B. food

C. the bikes

D. the fruit

3. Peter runs to another room to get some bags of rice because _______.[ ]

A. his father asks him to carry some

B. the shopkeeper wants to cook the meal

C. the shelves are full of rice

D. the shelves for rice are empty

4. The bags are _______. [ ]

A. easy to reach for Peter

B. too high for Peter to reach

C. on top of the boxes

D. very heavy

5. Peter falls down because _______. [ ]

A. he is on the boxes behind the door and the boss pushes the door

B. the bags fall down

C. the shopkeeper is calling him

D. there's some rice on his head

多项选择题