具有我国自主知识产权的“歼-10”飞机的横空出世,证实了我国航空事业在飞速发展.

题型:计算题

问题:

具有我国自主知识产权的“歼-10”飞机的横空出世,证实了我国航空事业在飞速发展.而航空事业的发展又离不开风洞试验,简化模型如图a所示,在光滑的水平轨道上停放相距s0=10 m的甲、乙两车,其中乙车是风力驱动车.在弹射装置使甲车获得v0=40 m/s的瞬时速度向乙车运动的同时,乙车的风洞开始工作,将风吹向固定在甲车上的挡风板,从而使乙车获得了速度,测绘装置得到了甲、乙两车的v-t图象如图b所示,设两车始终未相撞.

(1)若风对甲、乙的作用力相等,求甲、乙两车的质量比;

(2)求两车相距最近时的距离.

考点:匀变速直线运动
题型:计算题

下列不能有效增强桩冠的固位的是()

A.延长冠桩的长度

B.减小根管壁锥度

C.增加粘结剂稠度

D.增加桩冠与根管壁的密合度

E.增大桩冠直径

题型:计算题

可起尿糖假阳性的是()

A.异烟肼、链霉素

B.肌酐、尿酸

C.水杨酸

D.葡萄糖醛酸

E.阿司匹林

题型:计算题

在()必须进行1次矿井通风阻力测定。

A、新矿井投产前

B、投产后的每3年

C、局部通风系统变化时

D、矿井通风系统有较大变化时

题型:计算题

I used to find notes left in the collection basket of the church, beautiful notes about my homilies(讲道)and about the writer’s thoughts on the daily readings. The (1) fascinated me. But it was a long time (2) I met the author of the notes.

One Sunday morning, I was (3) that someone was waiting for me in the office, a young woman who said she (4) all the notes. When I saw her I was (5) , since I had no idea thatit was she who wrote the notes. She was sitting in a chair in the office. Her (6) was bowed and when she raised it to look at me, she could barely (7) without pain. Her face was disfigured(畸形), so smiling was very (8) for her. We (9) for a while that Sunday morning and agreed to meet for lunch later that week. As it (10) , we went to lunch several times, and we shared things about our (11) . We spoke of authors we both had (12) , and it was easy to tell that (13) are a great love of hers. She suffered from a disfigurement that cannot be made to look (14) . I know that her condition (15) her deeply. Yet there was a beauty to her that had nothing to do with (16) . She was one to be listened to, whose words came from a wounded but (17) heart. She possessed a fine tuned sense of beauty. Her only (18) in life was the loss of a friend. The truth of her life was a desire to see beyond the (19) for a glimpse of what it is that matters. She found beauty and (20) and they befriended her, and showed her what is real.

20().

A.success

B.hope

C.grace

D.help

题型:计算题

不属于Access为数据访问页提供的设计主题是( )。

A.冰川

B.波浪

C.常青树

D.现代

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