问题 填空题

某照明灯正常工作的电压是36V,正常发光时灯丝电阻为24Ω,则通过照明灯的电流是     A.如果电源电压是48V,为使照明灯正常发光,可以在电路中串联一个阻值为    Ω的电阻.

答案

1.5  8

题目分析:根据欧姆定律可计算照明灯的额定电流,根据串联电路电流和电压规律结合欧姆定律可计算串联电阻的阻值。I=串联电路各处电流相等,总电压等于各分电压之和。

R0

阅读理解

阅读理解。

     Being outgoing is good for your life.  rl'hose who are more outgoing like to meet lots of people and have more fun in life. In fact, being outgoing is not so hard as you think. Even shy people can be outgoing.

     You can start becoming outgoing with your best friend or a group of

friends.  But the real challenge comes when you meet strangers or new

friends. Smile more, and usually they will return your smile.  In this way, you may have some talks.

     Start a talk. Just a simple "Hello!" or "How is it going?" is a good start. If you want to make interesting talks, you should read news in newspapers and prepare your views, or surf the Internet for new information and then keep

that in mind.

     The easiest way to become more outgoing is to go out. This is also the

most important step. Go to a park, beach, club, party or any other place that

you think can be fun, and you may make new friends there.    

1. You should start to bP outgoing with____.

A. your parents    

B.your teachers    

C.your best friends  

D.your new friends

2. When you start a talk with a stranger, you should say "_         "

A. What's the matter?                        

B. What's your name?

C. How is it going?                          

D. Are you healthy?

3. The easiest way to be outgoing is -

A. talking      

B. smiling        

C. playing        

D. going out

4. Making new friends can make us ____________

A. more outgoing .    

B. healthier  

C. more athletic      

D. wilder

5. Which is NOT the writer's view?

A. Being outgoing is really difficult.

B. Being outgoing is good for our lives.

C. Being outgoing helps people have more fun.

D. Being outgoing with strangers is not easy.

选择题