问题 问答题 简答题

高压熔断器在电路中的作用原理如何?

答案

参考答案:

熔断器是电路或设备的保护元件。用于小负载配电线路和配电变压器的短路和过载保护。当短路电流流过熔断器时,将热元件本身加热熔断,从而使电路切断,以达到保护的目的。

阅读理解

阅读理解。

      A man went to a fast-food restaurant to buy his lunch."Hi," a worker said."May I help you?"

     "I'd like a hamburger, large chips, and a Coke," the man said.

     "Anything else?" the worker asked.

     "No," the man answered."That's it."

     "Is that for here or to go?" The worker asked.

     "To go," the man said.

     The worker put the man's lunch in a bag. The man took out his money and paid for his lunch.

     "Thank you," the worker said. "Have a nice day."

      The man took the bag and walked to a park. He sat down and opened the bag. He was surprised.

There was no hamburger in the bag. There were no chips. There was no Coke. There was only money

in the bag-a lot of money! The man counted the money. Two thousand dollars! Why was the money in the

bag? Where was the man's lunch?

     The manager of the fast-food restaurant needed to go to the bank. He put two thousand dollars in an

envelope (信封). He put the envelope in a bag and put the bag down. The worker gave the manager's bag to

the man by mistake. So the manager had a hamburger, chips and a Coke, and the man had two thousand

dollars. What should the man do?

1. The man went to a restaurant to __________.

A. buy his lunch

B. have a rest

C. sell drinks

D. cook food

2. The man wanted to have his lunch __________.

A. in a hotel

B. in a shop

C. in a restaurant

D. in a park

3. When the man opened the bag, he found __________ in it.

A. food

B. drink

C. money

D. nothing

4. _________ couldn't find his money.

A. The man

B. The manager

C. The worker

D. Nobody

选择题