问题 选择题

某人在距地面某一高度处以初速度v水平抛出一物体,落地速度大小为2v,则它在空中飞行的时间及距地面抛出的高度为(  )

A.

v
g
v2
2g

B.

3v
2g
9v2
4g

C.

3
v
2g
3v2
4g

D.

3v
g
3v2
2g

答案

落地时在竖直方向上的分速度vy=

(2v)2-v2
=
3
v
.则落地的时间t=
vy
g
=
3
v
g
,抛出的高度h=
1
2
gt2=
3v2
2g
.故D正确,A、B、C错误.

故选D.

阅读理解

根据描述为下列人物选择应该借鉴文章中的哪条建议(将相应数字序号填在横线上)

How to Make Friends

1. It’s hard to make friends if you stay home alone all the time. Get out of the house and do things that will put you in touch with other people. Join a club or play a sport. Attend meetings or other groups. It’s easier to make friends when you have similar interests.

2. Learn from people who seem to have lots of friends. Watch carefully how they make and keep friends. Don’t copy all of the things they do, but try to notice what they do. Then try some of those things yourself.

3. Don’t be afraid to show people what you’re really good at. Talk about the things you like and do best. Don’t hide your strong points. People will be interested in you if there is something interesting about you.

4. Plan things to talk about with people. Find out what’s in the newspaper headlines, listen to CDs, learn about what’s new with your favorite TV or movie star. The more you have to say, the more people will be interested in having a conversation with you

5. Look people in the eye when you talk to them. That way, they’ll find it easier to talk to you. It’s very difficult to have a conversation with people whose eyes are looking to the left, to the right, or at the floor. People may think you’re not interested in them and may stop being interested in you.

6. Be a good listener. Let people talk about themselves before talking about “me, me, me.” Ask lots of questions and show an interest in their answers.

____4_______a. Tony is never sure what to talk about when he meets people.

____________b. Rose wants to know why her classmate, Cindy, is so good at making friends.

____________c. Adam stays home every weekend and watches videos.

____________d. Benson is a very good dancer, but he never tells anyone about it.

____________e. Martha doesn’t care for others. She always talks about herself.

____________f. When Pedro feels uncomfortable talking to someone, he starts to look away.

a____4__;   b.________;    c._______;   d.______;   e.______;   f._______

单项选择题