问题 选择题

在真空中有a、b两个点电荷,b的电荷量是a的3倍,如果a受到的静电力是F,则b受到的静电力是(  )

A.F

B.

1
3
F

C.3F

D.4F

答案

电荷对b电荷的静电力与b电荷对a电荷的静电力是一对作用力与反作用力,大小相等.所以b受到的静电力是F.故A正确,B、C、D错误.

故选A.

多项选择题
阅读理解

He says the problem with teachers is, “What will a kid learn from someone who chose to become a teacher?” He reminds the other dinner guests that it’s true what they say about teachers: Those who can, do; those who can’t, teach.

I decide to bite my tongue instead of biting his and stop myself from reminding the other dinner guests that it’s also true what they say about lawyers-that they make money from the misfortune of others.

“I mean, you’re a teacher, Taylor,” he says to me.” Be honest. What do you make?”

I wish he hadn’t asked me to be honest, because now I have to teach him a lesson.

You want to know what I make?

I make kids work harder than they ever thought they could.

I can make a C+feel like a great achievement and an A-feel like a failure.

How dare you waste my time with anything less than your very best?

I make parents tremble in fear when I call them:

I hope I haven’t called at a bad time.

I just wanted to talk to you about something Billy said today.

Billy said, “Leave the kid alone. I still cry sometimes, don’t you?”

And it was the bravest act I have ever seen.

I make parents see their children for who they are and what they can be.

You want to know what I make?

I make kids wonder.

I make them question.

I make them criticise.

I make them think.

I make them apologise and mean it.

I make them write, write, write.

And then I make them read.

I teach them to solve math problems that they once thought impossible.

I make them understand that if you have brains then you follow your heart and if someone ever tries to judge you by what you make, you teach them a lesson.

Let me make this simple for you, so you know what I say is true:

I make a great difference! What about you?

小题1:What is the tone of the passage?

A.Upset and disappointed.

B.Cheerful and positive.

C.Angry and proud.

D.Humorous and light-hearted.小题2:What do we know about the man that the author is speaking to?

A.He dislikes lawyers.

B.He is actually a lawyer.

C.He is respectful to teachers.

D.He is in the author’s home.小题3:What’s the best title of this passage?

A.Requirements of a Good Teacher

B.An Argument Between Two Guests.

C.A Dinner Conversation

D.What Teachers Make小题4:The underlined phrase “bite my tongue” in Paragraph 2 is closest in meaning to       .

A.stop myself saying what I really think

B.say something that is wrong

C.speak out honestly but carelessly

D.keep silent about myself