【题目】如图是质谱仪的工作原理示意图。带电粒子被加速电场加速后,进入速度选择器。速度选择器内相互正交的匀强磁场和匀强电场的强度分别为B和E。平板S上有可让粒子通过的狭缝P和记录粒子位置的胶片A1A2。平板S下方有磁感应强度为B0的匀强磁场。下列表述正确的是( )
A.质谱仪是分析同位素的重要工具
B.速度选择器中的磁场方向垂直纸面向外
C.能通过狭缝P的带电粒子的速率等于
D.粒子打在胶片上的位置越靠近狭缝P,粒子的比荷越小
科目:高中地理 来源: 题型:
【题目】 短文改错(共10小题;每小题l分,满分10分)
假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。
增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。
删除:把多余的词用斜线(\)划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:
1. 每处错误及其修改均仅限一词;
2. 只允许修改10处,多者(从第11处起)不计分。
Living in the city, people have certain widely acknowledging advantages. They enjoy various entertainments. Besides, there are many culture activities. Also, people in the city had access to better information service and educational facilities, and many problems exist. The overcrowded population, traffic jam and other issues may resulted in nervousness and diseases. As for the country life, the first feeling crowding our minds are peace and quiet. In the countryside, people live quiet life. They are exposed to less noises and pollution. The air in the countryside is a lot of fresher than that in the city. Of course, life in the countryside is not perfect, too.
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科目:高中地理 来源: 题型:
【题目】有一灯泡上标有“6 V 0.1 A”字样,现要测绘该灯泡的伏安特性曲线,有下列器材可供选用
A.电压表(0~5 V,内阻2.0 kΩ)
B.电压表(0~10 V,内阻3.0 kΩ)
C.电流表(0~100m A,内阻2.0 Ω)
D.电流表(0~6 A,内阻1.5 Ω)
E.滑动变阻器(30 Ω,2 A)
F.滑动变阻器(100 Ω,0.5 A)
G.学生电源(直流9 V)及开关、导线等
(1)实验中所用的电压表应选________,电流表应选________,滑动变阻器应选________。
(2)画出实验电路图,要求电压从零开始测量。
(3)根据你的实验电路,将图中所示的器材连成实验电路。
(4)该同学描绘出的IU图像应是图中的________。
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科目:高中地理 来源: 题型:
【题目】短文改错
假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。错误涉及一个单词的增加、删除或修改。
增加:在缺词处加一个漏词符号(∧),并在其下面写出该加的词。
删除:把多余的词用斜线(\)划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:
1. 每处错误及其修改均仅限一词;
2. 只允许修改10处,多者(从第11处起)不计分。
Mr. Johnson is a hardworking teacher. Every day, he spends too much time with his work. With little sleep and hardly any break, so he works from morning till night. Hard work have made him very ill. "He has ruined his healthy. We are worried about him." That is which other teachers say. Yesterday afternoon, I paid visit to Mr. Johnson. I was eager to see him, but outside her room I stopped. I had to calm myself down. Quietly I step into the room. I saw him lying in bed, looking at some of the picture we had taken together. I understood that he missed us just as many as we missed him.
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科目:高中地理 来源: 题型:
【题目】如图所示是一种利用电磁原理制作的充气泵的结构示意图。其工作原理类似于打点计时器,当电磁铁通入电流时,可吸引或排斥上部的小磁铁,从而带动弹性金属片对橡皮碗下面的气室施加力的作用,达到对外充气的效果。请回答以下问题:
(1)当电流从电磁铁的接线柱a流入时,发现吸引小磁铁向下运动,则电磁铁的上端为________极,小磁铁的下端为________极。
(2)你认为这种充气泵是利用直流电好,还是利用交流电好?答案:________
(3)缠绕电磁铁用的铁芯可分为硬磁性材料和软磁性材料。硬磁性材料在磁场撤去后还会有很强的磁性,而软磁性材料在磁场撤去后就没有明显的磁性了。你认为这种铁芯最好用________材料制作。
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科目:高中地理 来源: 题型:
【题目】短文改错
假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文。文中共有10处语言错误,每句中最多有两处。错误涉及一个单词的增加、删除或修改。
增加:在缺词处加一个漏词符号(∧),并在其下面写出该加的词。
删除:把多余的词用斜线(\)划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:
1. 每处错误及其修改均仅限一词;
2. 只允许修改10处,多者(从第11处起)不计分。
Dear guests,
On behalf of our school, I would like to express our warm welcome to you. We are luck to have you here in middle of our English Week Activities. As planning, we have English Talent Show today. The purpose of this program was to develop our interest in English learning and practically abilities in listening and speaking. The program consists in the following activity: recitation, singing, word spelling, storytelling and so on. The show will begin at two o’clock this afternoon at the Student Centre. Dear guests, we are welcome to take part in some activities. I hope we students will be benefit from your presence but I sincerely wish you a pleasant time with us.
Thank you.
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科目:高中地理 来源: 题型:
【题目】A、B两滑块在同一光滑的水平直导轨上相向运动发生碰撞(碰撞时间极短).用闪光照相,闪光4次摄得的闪光照片如图所示.已知闪光的时间间隔为Δt,而闪光本身持续时间极短,在这4次闪光的瞬间,A、B两滑块均在0~80 cm刻度范围内,且第一次闪光时,滑块A恰好通过x=55 cm处,滑块B恰好通过x=70 cm处,问:
(1)碰撞发生在何处?
(2)碰撞发生在第一次闪光后多长时间?
(3)设两滑块的质量之比为mA∶mB=2∶3,试分析碰撞前后两滑块的质量与速度乘积之和是否相等?
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科目:高中地理 来源: 题型:
【题目】为确认HCl、H2CO3、H2SiO3的酸性强弱,某学生设计了如下图所示的实验装置,一次实验即可达到目的(不必选其他酸性物质)。请据此回答:
(1)锥形瓶中装某可溶性正盐溶液,分液漏斗所盛试剂应为________。
(2)装置B所盛的试剂是__________,其作用是__________________________________。
(3)装置C所盛试剂是________,C中反应的离子方程式是______________________________________。
(4)由此得到的结论是酸性:________>________>________。
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