中考真题 北师大版3
罗湖中学北师大版数学中考样卷3(附答案)
1/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------罗湖中学北师大版数学中考样卷3（附答案） 一、选择题1. 下列图形是正方体的表面展开图的是（ ）2. 下列事件中为必然事件的是（ ）A ．早晨的太阳一定从东方升起 B.打开数学课本时刚好翻到第60页 Ｃ.从一定高度落下的图钉，落地后钉尖朝上 Ｄ.今年14岁的小云一定是初中学生3. 将一副三角板如图放置，使点A 在DE 上，BC DE ∥，则AFC ∠的度数为（ ）A.45°B. 50°C. 60°D. 75°4.函数y =x 的取值范围是（ ） A.1x -≥ B. 1x >-C. 1x -≥且0x ≠D. 1x >-且0x ≠5. 方程()12xx -=的解是（ ）A.1x =-B. 2x =-C. 1212x x ==-，D.1212x x =-=，6. 某品牌服装折扣店将某件衣服按进价提高50%后标价，再打8折（标价的80%）销售，售价为240元.设这件衣服的进价为x 元，根据题意，下面所列的方程正确的是（ ）A ．50%80%240x ⨯=· B.()150%80%240x +⨯=· C.24050%80%x ⨯⨯= D. ()150%24080%x +=⨯·7. 学剪五角星：如图，先将一张长方形纸片按图①的虚线对折，得到图②，然后将图②沿虚线折叠得到图③，再将图③沿虚BC 剪下ABC △，展开即可得到一个五角星.如果想得到一个正五角星（如图④），那么在图③中剪下ABC △时，应使ABC ∠的度数为（ ）A ．B ．C ．D ．ADCBFE2/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------A.126°B. 108°C. 100°D. 90°8. 在四张完全相同的卡片上分别印有等边三角形、平行四边形、等腰梯形、圆的图案，现将印有图案的一面朝下，混合后从中一次性随机抽取两张，则抽到的卡片上印有的图案都是轴对称图形的概率为（ ） A ．14 B. 13 C. 12 D. 349. 如图，反比例函数()0ky x x=>的图象经过矩形OABC 对角线的交点M ，分别与AB BC 、相交于点.D E 、若四边形ODBE 的面积为6，则k 的值为（ ）A ．1 B. 2 C. 3 D. 410. .如图，梯形ABCD 中，AD BC ∥，点E 在BC 上，AE BE =，点F 是CD 的中点，且AF AB ⊥，若 2.746AD AF AB ===，，，则CE 的长为（ ）A．B. 1C. 2.5D. 2.311. 计算－（－5）的结果是（ ）．（A ）5 （B ）－5 （C ）15 （D ）－15二、填空题75a b c a +=-=，，设S a b c=++的值为___________. ，点E F 、分别在AB 和AC 上，CE D 为BF 的中点，AE AF :的值为① ②③④B ADFCEA F3/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------14.x 取值范围是＿＿＿＿＿＿．15. 如图，□ABCD 中，点A 关于点O 的对称点是点＿＿＿＿．16. 在“抛掷正六面体”的试验中，如果正六面体的六个面分别标有数字“1”、“2”、“3”、“4”、“5”和“6”，如果试验的次数增多，出现数字“1”的频率的变化趋势是＿＿＿＿＿＿＿＿＿＿＿．17. 如果方程2430x x -+=的两个根分别是Rt △ABC 的两条边，△ABC 最小的角为A ，那么tan A 的值为＿＿＿＿＿＿＿．三、计算题18. 已知()1012cos 451201013a b c d π-⎛⎫==+=-= ⎪⎝⎭，°，，（1）请化简这四个数；（2）根据化简结果，列式表示这四个数中“有理数的和”与“无理数的积”的差，然后计算结果.四、证明题19. 如图，在Rt ABC △中，90C ∠=°，点E 在斜边AB 上，以AE 为直径的O ⊙与BC 相切于点.D（1）求证：AD 平分.BAC ∠ （2）若3 4.AC AE ==，①求AD 的值；②求图中阴影部分的面积.4/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------五、应用题20. 学校为了解学生参加体育活动的情况，对学生“平均每天参加体育活动的时间”进行了随机抽样调查，下图是根据调查结果绘制的两幅不完整的统计图.请你根据统计图提供的信息，解答以下问题：（1）“平均每天参加体育活动的时间”“为0.5~1小时”部分的扇形统计图的圆心角为______度；（2）本次一共调查了_________名学生； （3）将条形统计图补充完整；（4）若该校有2000名学生，你估计全校可能有多少名学生平均每天参加体育活动的时间在0.5小时以下.21. 为建设“宜居宜业宜游”山水园林式城市，内江市正在对城区沱江河段进行区域性景观打造.如图，某施工单位为测得某河段的宽度，测量员先在河对岸边取一点A ，再在河这边沿河取两点B C 、，在点B 处测得点A 在北偏东30°方向上，在点C 处测得点A 在西北方向上，量得BC 长为200米.请你求出该河段的宽度（结果保留根号）.22. 一家蔬菜公司收购到某种绿色蔬菜140吨，准备加工后进行销售，销售后获利的情况如下表所示：已知该公司的加工能力是：每天能精加工5吨或粗加工15吨，但两种加工不能同时进行.受季节等条件的限制，公司必须在一定时间内将这批蔬菜全部加工后销售完.（1）如果要求12天刚好加工完140吨蔬菜，则公司应安排几天精加工，几天粗加工？（2）如果先进行精加工，然后进行粗加工.5/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------①试求出销售利润W 元与精加工的蔬菜吨数m 之间的函数关系式；②若要求在不超过10天的时间内，将140吨蔬菜全部加工完后进行销售，则加工这批蔬菜最多获得多少利润？此时如何分配加工时间？六、复合题23. 如图，△ABC 内接于⊙O ，且∠B = 60︒．过点C 作圆的切线l 与直径AD 的延长线交于点E ，AF ⊥l ，垂足为F ，CG ⊥AD ，垂足为G ． （1）求证：△ACF ≌△ACG ；（2）若AF = 43，求图中阴影部分的面积．七、开放题24. 阅读理解：我们知道，任意两点关于它们所连线段的中点成中心对称，在平面直角坐标系中，任意两点()()1122P x y Q x y ，、，的对称中心的坐标为1212.22x x y y ++⎛⎫⎪⎝⎭，观察应用：（1）如图，在平面直角坐标系中，若点()()120123P P -、，的对称中心是点A ，则点A 的坐标为_________；（2）另取两点()()1.62.110.B C --，、，有一电子青蛙从点1P 处开始依次关于点A B C 、、作循环对称跳动，即第一次跳到点1P 关于点A 的对称点2P 处，接着跳到3P 关于点C 的对称点4P 处，第四次再跳到点5处，…则点38P P 、的坐标分别为_________、（3）求出点2012P 的坐标，并直接写出在x 轴上与点2012P 、点C 构成等腰三角形的点的坐标.6/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------八、猜想、探究题25. 如图，抛物线y = ax 2+ bx + 4与x 轴的两个交点分别为A （－4，0）、B （2，0），与y 轴交于点C ，顶点为D ．E （1，2）为线段BC 的中点，BC 的垂直平分线与x 轴、y 轴分别交于F 、G ．（1）求抛物线的函数解析式，并写出顶点D 的坐标；（2）在直线EF 上求一点H ，使△CDH 的周长最小，并求出最小周长； （3）若点K 在x 轴上方的抛物线上运动，当K 运动到什么位置时， △EFK 的面积最大？并求出最大面积．26. 如图，A C D△和BCE △都是等腰直角三角形，90ACD BCE AE ∠=∠=°，交CD 于点F BD ，分别交CE AE 、于点.G H 、试猜测线段AE 和BD 的数量和位置关系，并说明理由.A7/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------一、选择题第1题答案.C第2题答案.A第3题答案.D第4题答案.C第5题答案.D第6题答案.B第7题答案.A第8题答案.C第9题答案.B第10题答案.D第11题答案.A二、填空题第12题答案.7第13题答案.12第14题答案.1x ≥第15题答案.C第16题答案.接近16第17题答案.13或48/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------三、计算题第18题答案.解：（1）11()33n -==，2cos 45121b =+=+°1=，0(2010π)c =- 1=，11d =-=4分（2）a c ，为有理数，b d ，为无理数，5分311)a c bd ∴+-=+-6分=4(21)3--= 7分四、证明题第19题答案.（1）证明：连接OD ，则O A O D=，DAO ODA ∴∠=∠. 1分BC 是O ⊙的切线， .OD BC ∴⊥AC BC OD AC ∴⊥，∥，2分 .CAD ODA ∴∠=∠DAO CAD AD ∴∠=∠∴，平分.BAC ∠4分 （2）①连结ED ，AE 为直径，90ADE C ∴∠=∠=°． 又由（1）知DAO CAD ADE ACD ∠=∠∴，△∽△，6分 AD ACAE AD∴=， 7分34AC AE ==，，23412AD AE AC ∴==⨯=·，AD ∴==②在Rt ADE △中，cos 42AD DAE AE ∠=== 30DAE ∴∠=°．120 2.AOD DE ∴∠==°，111222AOD ADE S S AD DE ∴==⨯=△△·2120π24π.3603AOD S ⨯=扇形=4π3AOD AOD S S S ∴-=△阴影扇形= 12分五、应用题第20题答案. 解：（1）54（2）2007分100=（人） 9分BC⊥于点D. 1分90306045ACD=-=∠=°°°，°．2分ACD CAD∴∠=∠，200.AD=-4分tanADABDBD∠=，(200)tan60)ABD AD AD∠=-=-·°．7分300=-9分答：该河段的宽度为（300-.第22题答案.解：（1）设应安排x天进行精加工，y天进行粗加工，根据题意得12515140.x yx y+=⎧⎨+=⎩，解得48.xy=⎧⎨=⎩，答：应安排4天进行精加工，8天进行粗加工.（2）①精加工m吨，则粗加工（140m-）吨，根据题意得20001000(140)W m m=+-=1000140000m+②要求在不超过10天的时间内将所有蔬菜加工完，14010515m m-∴+≤解得5m≤05m∴<≤又在一次函数1000140000W m=+中，10000k=>，W∴随m的增大而增大，∴当5m=时，5140000145000.W⨯+=最大=1000∴精加工天数为55÷=1，粗加工天数为(1405)159-÷=．∴安排1天进行精加工，9天进行粗加工，可以获得最多利润为1450009/1110/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------元. 10分六、复合题第23题答案.（1）如图，连结CD ，OC ，则∠ADC =∠B = 60︒． ∵ AC ⊥CD ，CG ⊥AD ，∴ ∠ACG =∠ADC = 60︒．由于 ∠ODC = 60︒，OC = OD ，∴ △OCD 为正三角形，得 ∠DCO = 60︒． 由OC ⊥l ，得 ∠ECD = 30︒，∴ ∠ECG = 30︒ + 30︒ = 60︒． 进而 ∠ACF = 180︒－2×60︒ = 60︒，∴ △ACF ≌△ACG ． （2）在Rt △ACF 中，∠ACF = 60︒，AF = 43，得 CF = 4． 在Rt △OCG 中，∠COG = 60︒，CG = CF = 4，得 OC =38． 在Rt △CEO 中，OE =316．于是 S 阴影 = S △CEO －S 扇形COD =36060212OC CG OE ⋅-⋅π=9)33(32π-．七、开放题第24题答案.解：（1）（1，1） 2分 （2）（5.21-，） 4分 （2，3） 6分 （3）1(01)P ，-→2(23)P ，→3( 5.21.2)P -，→4(3.2 1.2)P -，→5( 1.23.2)P -，→6(21)P -，→7(01)P -，→8(23)P ，…∴7P 的坐标和1P 的坐标相同，8P 的坐标和2P 的坐标相同，即坐标以6为周期循环.20126÷=335…2，2012P ∴的坐标与2P 的坐标相同，为2012(23)P ，；在x 轴上与点2012P 、点C 构成等腰三角形的点的坐标为(20)10)(50)，，，， 12分 （1）由题意，得 ⎩⎨⎧=++=+-,0424,04416b a b a 解得21-=a ，b =－1．所以抛物线的解析式为4212+--=x x y ，顶点D 的坐标为（－1，29）．（2）设抛物线的对称轴与x 轴交于点M ．因为EF 垂直平分BC ，即C 关于直线EG 的对称点为B ，连结BD 交于EF 于一点，则这一点为所求点H ，使DH + CH 最小，即最小为 DH + CH = DH + HB = BD =132322=+DM BM ． 而11/11班级_____________________ 姓名________ 考场号_____ 考号_____---------------------------------------密--------------------封---------------------线------------------------------------25)429(122=-+=CD ． ∴ △CDH 的周长最小值为CD + DR + CH =21335+． 设直线BD 的解析式为y = k 1x + b ，则 ⎪⎩⎪⎨⎧=+-=+,29,021111b k b k 解得 231-=k ，b 1 = 3． 所以直线BD 的解析式为y =23-x + 3． 由于BC = 25，CE = BC ∕2 =5，Rt △CEG ∽△COB ， 得 CE : CO = CG : CB ，所以 CG = 2.5，GO = 1.5．G （0，1.5）．同理可求得直线EF 的解析式为y =21x +23．联立直线BD 与EF 的方程，解得使△CDH 的周长最小的点H （43，815）． （3）设K （t ，4212+--t t ），x F ＜t ＜x E ．过K 作x 轴的垂线交EF 于N ．则 KN = y K －y N =4212+--t t －（21t +23）=2523212+--t t ．所以 S △EFK = S △KFN + S △KNE =21KN （t + 3）+21KN （1－t ）= 2KN = －t 2－3t + 5 =－（t +23）2 +429．即当t =－23时，△EFK 的面积最大，最大面积为429，此时K （－23，835）．第26题答案.解：猜测 AE BD AE BD =，⊥．2分理由如下：90ACD BCE ∠=∠=°，ACD DCE BCE DCE ∴∠+∠=∠+∠，即.ACE DCB ∠=∠ ACD ∴△和BCE △都是等腰直角三角形.AC CD CE CB ∴==，， ACE DCB ∴△≌△．AE BD ∴=，.CAE CDB ∠=∠90AFC DFH DHF ACD ∠=∠∴∠=∠=，°．AE BD ∴⊥．9分。
初三数学中考试卷(北师大版,含答案)
初三数学中考试卷一、选择题(本题共10个小题，每小题4分，共40分。
请选出各题中其中一个符合题意的正确选项，不选、多选、错选均不给分)1．冬季的一天，室内温度是8℃，室外温度是－2℃，则室内外温度相差( )A、4℃B、6℃C、10℃D、16℃2．一个不透明的袋中装有除颜色外其余均相同的5个红球和3个黄球，从中随机摸出一个，则摸到黄球的概率是（）A、 B、 C、 D、3．右图中几何体的正视图是( )4．吋是电视机常用规格之一，1吋约为拇指上面一节的长，则7吋长相当于( )A、课本的宽度B、课桌的宽度C、黑板的高度D、粉笔的长度5．已知⊙O的直径AB与弦AC的夹角为35°，过C点的切线PC与AB的延长线交于点P，则∠P等于( )A、15°B、20°C、25°D、30°6．如图，设M、N分别是直角梯形ABCD两腰AD、CB的中点，DE⊥AB于点E，将△ADE沿DE翻折，M与N恰好重合，则AE∶BE等于( )A、2∶1B、1∶2C、3∶2D、2∶37．不等式的解集是( )A、 B、 C、 D、8．若有一条公共边的两个三角形称为一对“共边三角形”，则图中以BC为公共边的“共边三角形”有( )A、2对B、3对C、4对D、6对9．小敏在某次投篮中，球的运动线路是抛物线的一部分(如图)，若命中篮圈中心，则他与篮底的距离l是( )A、3.5mB、4 mC、4.5 mD、 4.6 m10．如图，正方形OABC，ADEF的顶点A，D，C在坐标轴上，点F在AB上，点B，E 在函数的图象上，则点E的坐标是( )A、 B、C、 D、二、填空题(本题有6小题，每小题5分共30分)11．当______________时，分式的值为0.12.据媒体报道，今年“五一”黄金周期间，我市旅游收入再创历史新高，达1290000000元，用科学记数法表示为______________元.13．如图是小敏五次射击成绩的图，根据图示信息，则此五次成绩的平均数是_____________环。
2024年北师大版中考物理试题及解答参考
2024年北师大版物理中考自测试题(答案在后面)一、单项选择题（本大题有10小题，每小题3分，共30分）1、下列关于速度的说法正确的是：A、速度是表示物体运动快慢的物理量，单位是米每秒（m/s）。
B、速度越大，物体运动越慢。
C、速度为零时，物体一定处于静止状态。
D、物体的速度为零，但加速度不为零。
2、一个物体在水平面上做匀速直线运动，下列说法正确的是：A、物体的速度一定为零。
B、物体的加速度一定为零。
C、物体的合外力一定为零。
D、物体受到的摩擦力一定为零。
3、在下列哪个情况下，物体的动能是零？A、物体在水平面上匀速直线运动B、物体从静止开始自由下落C、物体在竖直方向上做匀速上升运动D、物体在水平面内做匀速圆周运动4、一个物体在水平面上受到一个大小为10N的力作用，如果物体在水平面上做匀速直线运动，那么物体所受的摩擦力大小是多少？A、0NB、5NC、10ND、无法确定5、一个物体在水平面上做匀速直线运动，若突然受到一个水平向左的摩擦力作用，物体将会发生什么现象？A、速度逐渐增大B、速度逐渐减小C、运动方向改变D、运动状态不变6、下列关于光的传播特性的描述中，正确的是：A、光在同种均匀介质中沿直线传播B、光在真空中的传播速度小于在空气中的传播速度C、光从空气进入水中时，光的传播速度增加D、光从水中进入空气时，光的传播方向不会发生改变7、一个物体在水平面上做匀速直线运动，下列说法正确的是：A、物体的速度不变，加速度为0。
B、物体的速度不变，加速度不为0。
C、物体的速度在减小，加速度为负。
D、物体的速度在增大，加速度为正。
8、一个物体在水平方向上受到两个力的作用，一个向东，一个向西，且大小相等，那么：A、物体一定静止。
B、物体一定做匀速直线运动。
C、物体的运动状态取决于受力时间。
D、物体可能静止，也可能做匀速直线运动。
9、一个物体从静止开始做匀加速直线运动，3秒内通过的路程是18米，那么物体的加速度是：A. 2 m/s²B. 3 m/s²C. 4 m/s²D. 5 m/s²二、多项选择题（本大题有2小题，每小题3分，共6分）1、题干：下列现象中，属于能量转换的是：A、水从高处流向低处，水轮机转动B、电能通过加热使灯泡发光C、摩擦生热使物体温度升高D、物体从高处落下，速度越来越快2、题干：关于光的传播和折射现象，下列说法正确的是：A、光在同种均匀介质中沿直线传播B、光从空气斜射入水中时，折射角大于入射角C、光从水中斜射入空气中时，折射角小于入射角D、光从一种透明介质斜射入另一种透明介质时，传播方向会发生改变三、填空题（本大题有5小题，每小题4分，共20分）1、在匀速直线运动中，物体在单位时间内通过的路程称为速度。
初三中考数学试卷北师大版
一、选择题（每题3分，共30分）1. 下列各数中，绝对值最小的是（）A. -3B. 0C. 1D. -22. 若m，n是方程x^2-3x+2=0的两个根，则m+n的值是（）A. 2B. 3C. 4D. 53. 已知等腰三角形底边长为6cm，腰长为8cm，则该三角形的周长为（）A. 18cmB. 20cmC. 22cmD. 24cm4. 若a^2=4，b^2=9，则a+b的值为（）A. 5B. -5C. 13D. -135. 下列函数中，定义域为实数集的是（）A. y=√(x-1)B. y=|x|C. y=1/xD. y=x^26. 若a，b，c是等差数列，且a+b+c=12，b=4，则c的值为（）A. 2B. 4C. 6D. 87. 下列各式中，有理数平方根为整数的是（）A. (-1/2)^2B. (-3/2)^2C. (-2/3)^2D. (-1/3)^28. 下列函数中，是奇函数的是（）A. y=x^2B. y=|x|C. y=x^3D. y=x^49. 下列各式中，对数式有意义的是（）A. log2(-3)B. log2(1/2)C. log2(0)D. log2(∞)10. 若|a|=5，|b|=3，则|a-b|的取值范围是（）A. [2,8]B. [2,5]C. [5,8]D. [5,12]二、填空题（每题3分，共30分）11. 若x^2-5x+6=0，则x的值为______。
12. 若a，b，c是等差数列，且a+b+c=12，b=4，则公差d的值为______。
13. 已知等腰三角形底边长为6cm，腰长为8cm，则该三角形的面积为______cm^2。
14. 若a^2=4，b^2=9，则a+b的值为______。
15. 下列函数中，定义域为实数集的是______。
16. 若a，b，c是等差数列，且a+b+c=12，b=4，则c的值为______。
17. 下列各式中，对数式有意义的是______。
初中北师大版数学中考试卷
1. 下列各数中，正数是（）A. -2.5B. 0.1C. -1.2D. 02. 已知a=5，b=-3，则a-b的值是（）A. 2B. -2C. 8D. -83. 一个长方形的长是6厘米，宽是4厘米，它的面积是（）A. 24平方厘米B. 20平方厘米C. 12平方厘米D. 18平方厘米4. 下列各图中，不是平行四边形的是（）A. 图1B. 图2C. 图3D. 图45. 若x=3，则代数式2x-5的值是（）A. 1B. 4C. 7D. 86. 下列各数中，有理数是（）A. √4B. √-1C. πD. √07. 一个等腰三角形的底边长为8厘米，腰长为10厘米，则这个三角形的周长是（）A. 24厘米B. 26厘米C. 28厘米D. 30厘米8. 下列各式中，正确的是（）A. 2x + 3 = 5x - 2B. 3a - 4 = 2a + 1C. 5b + 6 = 4b + 9D. 4c - 7 = 3c - 89. 下列各式中，同类项是（）A. x^2B. 2xC. 3x^2D. 4x10. 下列各图中，能组成直角三角形的是（）A. 图1B. 图2C. 图3D. 图411. 如果x=2，那么2x-3的值是______。
12. 一个数的相反数是它的______。
13. 下列各数中，负数是______。
14. 一个等边三角形的边长是______。
15. 一个圆的半径是5厘米，它的直径是______。
16. 下列各数中，有理数是______。
17. 一个长方体的长、宽、高分别是6厘米、4厘米、3厘米，它的体积是______。
18. 下列各式中，同类项是______。
19. 下列各式中，正确的是______。
20. 下列各图中，能组成直角三角形的是______。
三、解答题（每题10分，共30分）21. 解方程：3x - 2 = 7。
22. 已知a=5，b=-3，求a^2 - b^2的值。
23. 一个长方形的长是8厘米，宽是6厘米，求它的面积。
初三中考数学试卷北师大版
1. 若a，b，c成等差数列，且a+b+c=12，b=4，则c的值为（）A. 2B. 4C. 6D. 82. 在平面直角坐标系中，点A（2，3）关于y轴的对称点为B，则点B的坐标为（）A.（-2，3）B.（2，-3）C.（-2，-3）D.（2，3）3. 已知一次函数y=kx+b（k≠0）的图象经过点（1，2）和（-1，0），则该函数的解析式为（）A. y=3x+1B. y=-3x+1C. y=3x-1D. y=-3x-14. 若等差数列{an}的公差为d，首项为a1，第n项为an，则an=（）A. a1+(n-1)dB. a1+(n+1)dC. a1-(n-1)dD. a1-(n+1)d5. 已知正方体的对角线长为3，则该正方体的表面积为（）A. 9B. 12C. 15D. 186. 在等腰三角形ABC中，AB=AC，若∠BAC=60°，则∠B=（）A. 30°B. 45°C. 60°D. 90°7. 已知函数f(x)=x^2-2x+1，则f(-1)=（）A. 0B. 1C. 2D. 38. 若二次函数y=ax^2+bx+c（a≠0）的图象开口向上，且a+b+c=0，则a的取值范围为（）A. a>0B. a<0C. a≥0D. a≤09. 已知等比数列{an}的公比为q，首项为a1，第n项为an，则an=（）A. a1q^(n-1)B. a1q^(n+1)C. a1q^(1-n)D. a1q^(n-2)10. 在平面直角坐标系中，点P（2，3）到直线x+y-5=0的距离为（）A. 1B. 2C. 3D. 411. 已知等差数列{an}的首项为a1，公差为d，则第n项an=______。
12. 在平面直角坐标系中，点A（1，2）关于x轴的对称点为B，则点B的坐标为______。
13. 若二次函数y=ax^2+bx+c（a≠0）的图象开口向上，且a+b+c=0，则a的取值范围为______。
北师大版英语中考试题与参考答案(2025年)
2025年北师大版英语中考复习试题与参考答案一、听力部分（本大题有20小题，每小题1分，共20分）1、Listen to the following dialogue and answer the question.A: Good morning! Can you help me find the English section?B: Sure, it’s on the second floor. The signs will lead you there.Question: Where does the English section of the library located?A) On the first floorB) On the second floorC) On the third floorD) On the ground floorAnswer: BExplanation: The speaker B indicates that the English section is located on the second floor, so the correct answer is B) On the second floor.2、Listen to the following short passage and choose the best answer to the question.Passage: The summer solstice is the longest day of the year in the Northern Hemisphere, occurring around June 21st. It’s a time when the sun reaches its highest point in the sky, marking the beginning of summer. Many cultures celebrate this day with festivals and traditional activities.Question: What is the significance of the summer solstice in the NorthernHemisphere?A) It’s the shortest day of the year.B) It marks the beginning of winter.C) It’s the day with the longest daylight hours.D) It’s a time to plant crops.Answer: CExplanation: The passage explicitly states that the summer solstice is the longest day of the year, which means it has the longest daylight hours. Therefore, the correct answer is C) It’s the day with the longest daylight hours.3、听力原文：W: Hello, John. How was your weekend?M: Oh, it was great! I went hiking with my friends. We climbed up a mountain and enjoyed the beautiful scenery.Questions:1.What did John do last weekend?2.How did John feel about his weekend?Answer:1.John went hiking with his friends.2.John felt great about his weekend.Explanation:This question asks about John’s weekend activities. According to the dialogue, John went hiking with his friends, so the answer is “John went hiking with his friends.” The second question asks about John’s feelings towards his weekend.The dialogue indicates that he felt great, so the answer is “John felt great about his weekend.”4、听力原文：W: Hi, Mike. Are you planning to go to the cinema this weekend?M: Yeah, I’m thinking about watching a horror movie. I haven’t seen one in a while.Questions:1.What is Mike planning to do this weekend?2.What type of movie does Mike want to watch?Answer:1.Mike is planning to go to the cinema.2.Mike wants to watch a horror movie.Explanation:This question asks about Mike’s plans for the weekend. According to the dialogue, Mike is thinking about going to the cinema, so the answer is “Mike is planning to go to the cinema.” The second question asks about the type of movie Mike wants to watch. The dialogue mentions that he wants to watch a horror movie, so the answer is “Mike wants to watch a horror movie.”5、听力材料：A: Hi, John! Are you going to the library this weekend?B: Yes, I am. I need to borrow some books for my research project.A: That’s great. I’m also going to the library. I want to find some books about history.B: Cool! Let’s meet at the library around 10:00 am.Question: What are John and the speaker planning to do this weekend?A) Go shopping.B) Go to the library.C) Watch a movie.D) Go to the park.Answer: B) Go to the library.Explanation: In the dialogue, both John and the speaker mention that they are going to the library. This indicates that their plan for the weekend is to go to the library.6、听力材料：A: How was your day, Sarah?B: It was good, thanks. I had an English class in the morning, and then I went to the gym in the afternoon.A: That sounds like a busy day. Did you enjoy the gym?B: Yes, I did. The instructor was really helpful, and I met some new friends there.A: That’s nice. I should start going to the gym more often.B: You should! It’s a great way to stay healthy and meet new people.Question: What did Sarah do in the morning?A) She went to the gym.B) She had an English class.C) She went shopping.D) She watched a movie.Answer: B) She had an English class.Explanation: In the dialogue, Sarah mentions that she had an English class in the morning. This directly answers the question about what she did in the morning.7.What does the woman suggest the man do?A) Buy a new car.B) Take the bus.C) Repair his car.D) Sell his car.Answer: CExplanation: The correct answer is C because in the conversation, the woman advises the man that he should get his car fixed instead of buying a new one or taking other transportation options.8.How long has the man’s car been broken?A) One day.B) Two days.C) Three days.D) Four days.Answer: BExplanation: The correct answer is B. During their discussion, the manmentions that his vehicle has not been working for the past two days, which aligns with option B.9.You are listening to a conversation between two friends, Alex and Jamie. They are discussing their plans for the weekend.Alex: “Hey Jamie, do you have any plans for the weekend?”Jamie: “Well, I was thinking of going hiking. How about you?”Alex: “That sounds great! I haven’t been hiking in a while. What trail are you thinking of?”Jamie: “I was thinking of the Blue Ridge Trail. It’s not too far from here and offers some amazing views.”Alex: “Oh, I’ve heard about that trail. It’s supposed to be beautiful this time of year. I’m in!”Question: What is Alex’s response to Jamie’s suggestion?A) “I’m not interested in hiking.”B) “I’ve already made other plans.”C) “That sounds great! I haven’t been hiking in a while.”D) “I don’t know anything about hiking.”Answer: C) “That sounds great! I haven’t been hiking in a while.”Explanation: The correct answer is C because Alex responds positively to Jamie’s suggestion of going hiking and mentions that they haven’t been hiking in a while, which implies that they are interested in the idea.10.You are listening to a radio announcement about a local music festival.Announcer: “This weekend, the town of Maplewood is hosting the Maplewood Music Festival! There will be performances by local bands and international stars. The festival starts at 10 am on Saturday and runs until midnight. admission is free, but there will be food and drink available for purchase. For more information, visit our website at or call 555-1234.”Question: What time does the Maplewood Music Festival start on Saturday?A) 8 amB) 10 amC) 12 pmD) 2 pmAnswer: B) 10 amExplanation: The correct answer is B because the radio announcement clearly states that the Maplewood Music Festival starts at 10 am on Saturday.11、You will now hear a dialogue between a librarian and a student who is looking for a book on ancient history. Listen carefully and then choose the correct answer to the question you hear afterwards.Answer: This part is hypothetical, as the audio isn’t provided. In a real exam setting, students would listen and select the appropriate choice.Explanation: Since we don’t have the audio, we can’t provide a specific answer or explanation here. Normally, after listening, the student should be able to identify whether the book was found, what section it was in, or any otherdetail pertinent to the dialogue.12、Next, listen to a conversation between two friends discussing their weekend plans. One of them suggests going to a movie while the other proposes a picnic. Pay attention to which activity they ultimately decide on and why.Answer: Again, without the audio, we cannot give a precise answer. However, let’s assume the friends decide on the picnic because the weather forecast predicts sunny weather.Explanation: The dialogue likely included information about the weather conditions over the weekend, influencing their decision to opt for outdoor activities rather than staying indoors to watch a movie.13.Listen to the conversation between two students, and answer the question. Student A: Hey, do you know what the homework for tomorrow is?Student B: Yea h, it’s to read Chapter 4 in our textbook and write a summary.Question: What is the homework for tomorrow?A) To read Chapter 4 in the textbook.B) To write a summary of the book.C) To read Chapter 4 and write a summary.D) None of the above.Answer: C) To read Chapter 4 and write a summary.Explanation: The conversation clearly states that the homework for tomorrow is to read Chapter 4 in the textbook and write a summary, which is option C.14.Listen to the dialogue between a teacher and a student, and answer thequestion.Teacher: How was your trip to the science museum?Student: It was amazing! We got to see all sorts of cool exhibits, and I even got to conduct a little experiment.Question: What did the student do during their trip to the science museum?A) Watch movies.B) Conduct an experiment.C) Buy souvenirs.D) Attend a lecture.Answer: B) Conduct an experiment.Explanation: The student explicitly mentions conducting a little experiment during their trip to the science museum, which is option B.15、What is the main topic of the conversation between the student and the librarian?A)The process of checking out booksB)The rules of the libraryC) A discussion about a particular bookD)The opening hours of the libraryAnswer: B) The rules of the libraryExplanation: In the conversation, the librarian explains to the student the rules regarding the use of books within the library and borrowing procedures. This indicates that the primary focus was on library rules.16、According to the dialogue, what time does the library close on weekdays?A)5:00 PMB)6:00 PMC)7:00 PMD)8:00 PMAnswer: D) 8:00 PMExplanation: During the dialogue, the librarian mentions that the closing time for the library on weekdays is at 8:00 PM. The other options were not mentioned as closing times during the conversation.17.You are listening to a conversation between two students, Tom and Lucy, discussing their weekend plans.Tom: Hey Lucy, what are you doing this weekend?Lucy: I’m thinking of going hiking in the mountains. How about you, Tom? Tom: That sounds great! I was actually planning to visit the city museum. I heard it has some interesting exhibits.Lucy: Wow, I should check it out too. Maybe we can go together on Sunday.Question: What are Tom’s weekend plans?A) Going hiking in the mountains.B) Visiting the city museum.C) Attending a sports event.D) Going to a movie.Answer: BExplanation: Tom mentions that he is planning to visit the city museum, which indicates that his weekend plan is B) Visiting the city museum.18.You are listening to a short dialogue between a teacher and a student, Alice, discussing her project.Teacher: Alice, how are you progressing on your science project?Alice: I’m almost finished, Mr.Smith. I’ve collected all the data and now I’m working on the analysis.Teacher: That’s good to hear. Remember to include a clear introduction and conclusion in your report.Alice: Yes, I will. And I’m also planning to include some graphs to illustrate the data.Question: What is Alice currently working on?A) Writing a conclusion.B) Collecting more data.C) Analyzing the data.D) Preparing a presentation.Answer: CExplanation: Alice states that she is “working on the analysis,” which means she is currently in the process of analyzing the data, making option C) Analyzing the data the correct answer.19、What does the woman suggest the man should do?A. He should take a break from studying.B. He should continue studying hard.C. He should go to the movies with her.Answer: C. He should go to the movies with her.Explanation: In the conversation, the woman notices that the man has been studying for a long time and suggests he take a break and join her at the cinema. This indicates she’s inviting him to relax rather than keep working.20、Why can’t the ma n accept the invitation right away?A. He doesn’t want to go to the movies.B. He has more studying to complete.C. He already made plans with someone else.Answer: B. He has more studying to complete.Explanation: The man responds by saying he needs to finish his homework before he can consider taking a break, implying that he has responsibilities that need to be taken care of first before he can accept the invitation to the movies.二、阅读理解（30分）Reading ComprehensionPassage:The Great Wall of China is one of the most famous landmarks in the world. It was built over several centuries, starting in the 7th century BC. The wall’s primary purpose was to protect the Chinese empire from invasions by nomadic tribes from the north. It stretches over 13,000 miles and passes through various provinces in northern China.The construction of the Great Wall involved millions of workers, including soldiers, peasants, and artisans. It was built using a combination of materials, including bricks, stones, wood, and earth. The wall is known for its zigzagging design, which allowed it to adapt to the rugged terrain of the mountains.Over the years, the Great Wall has faced many challenges, including natural erosion and human destruction. However, efforts have been made to preserve and restore this historical marvel. Today, the Great Wall attracts millions of tourists from around the world each year, offering them a glimpse into ancient Chinese history and culture.Questions:1.What is the main purpose of the Great Wall of China?A) To serve as a tourist attraction.B) To protect the Chinese empire from invasions.C) To connect different provinces in China.D) To showcase the architectural skills of ancient China.2.What is the main material used in the construction of the Great Wall?A) Only bricks.B) Only stones.C) A combination of bricks, stones, wood, and earth.D) Only wood and earth.3.Why is the zigzagging design of the Great Wall significant?A) It made the wall more visually appealing.B) It was a result of the lack of planning.C) It allowed the wall to adapt to the mountainous terrain.D) It was a sign of military strategy.Answers:1.B) To protect the Chinese empire from invasions.2.C) A combination of bricks, stones, wood, and earth.3.C) It allowed the wall to adapt to the mountainous terrain.三、完型填空（15分）Section 3: Cloze TestRead the following passage and choose the best word for each blank from the options given below.In the small town of Willow Creek, the residents had always looked forward to the annual Willow Creek Festival. The festival was a time for celebration, where people from all over the country would gather to enjoy music, food, and various cultural activities. This year, however, the festival was threatened by a (1)___________situation.(1)a.unusualb.pleasantc.ordinaryd.dangerousThe problem was a (2)___________drought that had lasted for several months. Thelack of rain had affected both the crops and the water supply, leading to(3)___________concerns among the townspeople.(3)a.littleb.fewc.muchd.manyThe town’s mayor, Mr.Thompson, held an emergency meeting to discuss the situation. He proposed several (4)___________to help alleviate the drought, including asking for water donations from neighboring towns and implementing strict water-saving measures.(4)a.solutionsb.decisionsc.rulesd.suggestionsDespite the challenges, the festival organizers were determined not to cancel the event. They (5)___________creative ways to incorporate water conservation into the festival activities.(5)a.thoughtb.foundc.came up withd.createdAnswer Key:1.a. unusual2.b. severe3.c. much4.a. solutions5.c. came up with四、语法填空题（本大题有10小题，每小题1分，共10分）1、John_______(be) very busy recently because he’s been working on his new book.A. has beenB. isC. wasD. will beAnswer: A. has beenExplanation: The correct answer is “has been” because the sentence indicates a continuous action that started in the past and is still ongoing in the present. The phrase “recently” suggests a time frame that includes the present.2、If I_______(know) her, I would have invited her to the party.A. had knownB. knewC. knowD. am knowingAnswer: A. had knownExplanation: The correct answer is “had known” because the sentence is in the conditional perfect tense, which is used to express a past condition and its hypothetical result in the past. The structure “if I had + past participle” is used to talk about a past situation that did not happen.3、In the__________(1) __________, the students were actively participating in the science fair.A. momentB. timeC. secondD. minuteAnswer: AExplanation: The correct word to use here is “moment,” which refers to a short period of time, often one that is significant or memorable. The phrase “at that moment” implies a specific point in time during which the action (students participating in the science fair) was occurring.4、If you__________(1)__________to be honest, you should not have lied to your friend.A. wantB. would likeC. had wantedD. have wantedAnswer: CExplanation: The correct answer is “had wanted,” which is the past perfect tense. This tense is used to express a desire that was true at a past time, but did not come to pass. The sentence implies that the speaker is suggesting that the person should have wanted to be honest at some point in the past, which wouldhave prevented the lie from occurring.5、In the___________of the school, there is a beautiful garden where students often___________their breaks.A. middle, spendB. center, takeC. middle, haveD. center, makeAnswer: BExplanation: The correct phrase to describe the central part of a school is “the center of the school.” The correct verb to describe spending time during a break is “take,” as in “take their breaks.” Therefore, the correct answer is “B. center, take.”6、The___________of the book was so interesting that I couldn’t put it down until the___________was over.A. story, chapterB. title, endC. author, bookD. cover, summaryAnswer: BExp lanation: The “title” of a book refers to its name. The phrase “until the end” indicates the time when the book was finished. The other options do not fit the context as well. Therefore, the correct answer is “B. title, end.”7.In the__________(7) __________, the students are encouraged to speak English actively.Answer: 7. pastExplanation: The correct word to fill in the blank is “past” because the sentence is referring to a time when the students were encouraged to speak English actively, which is in the past. The phrase “in the past” is a common English expression used to talk about events or actions that happened before the present.8.If__________(8)__________you need help with your homework, don’t hesitate to ask the teacher.Answer: 8. youExplanation: The correct word to fill in the blank is “you” because the sentence is expressing a conditional statement. The structure “If + subject + verb” is used to introduce a condition, and “you” is the subject that would be performing the action of asking for help if the condition were met.9.In the 9 morning, we had a surprise visit from our old friend.A. lastB. nextC. firstD. pastAnswer: CExplanation: The correct answer is “first” because it indicates the first morning of the school year or a specific event, which fits the context of a surprise visit.10.If you 10 your homework now, you can watch TV later.A. finishedB. finishC. will finishD. are finishingAnswer: BExplanation: The correct answer is “finish” because the sentence is talking about a present condition that, if met, will allow the action of watching TV later. The simple present tense is used to express a general truth or a condition in the present.五、简答题（本大题有5小题，每小题2分，共10分）1、What are the main differences between a singular noun and a plural noun in English grammar?答案：1.Singular nouns refer to one person, place, thing, or idea, while plural nouns refer to more than one of the same person, place, thing, or idea.2.Singular nouns typically do not end with an ‘s’ or any other pluralizing suffix, whereas plural nouns often add an ‘s’, ‘es’, or another suffix to indicate plurality.3.The verb agreement is different; singular nouns require a singular verb, and plural nouns require a plural verb.解析：This question asks the student to identify and explain the key differences between singular and plural nouns. The answer outlines three main differences: the quantity they represent, the absence of pluralization in singular nouns,and the effect on verb agreement.3、What are the main differences between a present perfect tense and a past perfect tense?答案：The main differences between a present perfect tense and a past perfect tense are as follows:1.Time reference:•Present perfect tense: It is used to talk about actions or states that started in the past and continue to the present or have a present result.•Past perfect tense: It is used to describe an action that was completed before another past action.2.Time adverbs:•Pres ent perfect tense: It often uses time adverbs like “already,” “yet,”“just,” “recently,” etc.•Past perfect tense: It often uses time adverbs like “before,” “after,”“by,” “before then,” etc.3.Verb form:•Present perfect tense: The verb is formed with “have/has” + past participle.•Past perfect tense: The verb is formed with “had” + past participle.解析：This question tests the understanding of the present perfect and past perfect tenses. The answer outlines the key differences in terms of timereference, time adverbs, and verb forms, which are important aspects of these tenses in English grammar.4、How can you use the passive voice to express an action in which the subject is the recipient of the action?答案：To express an action where the subject is the recipient of the action using the passive voice, you can follow these steps:1.Identify the subject that is receiving the action.2.Change the subject to the object of the action.e the passive form of the verb, which is “be” (in its appropriate form) + past participle.For example:Active voice: “The students are teaching the lesson.”Passive voice: “The lesson is being taught by the students.”解析：This question examines the use of the passive voice to emphasize the recipient of the action rather than the doer. The answer provides a clear explanation of how to transform an active sentence into a passive one, highlighting the importance of identifying the subject as the recipient and using the correct form of the “be” verb followed by the past participle of the main verb.5、What are the main differences between present perfect tense and presentperfect continuous tense in English grammar?Answer: The main differences between present perfect tense and present perfect continuous tense in English grammar are as follows:1.Time reference:•Present perfect tense is used to express an action that started in the past and has a connection with the present.•Present perfect continuous tense is used to express an ongoing action that started in the past and is still continuing.2.Frequency:•Present perfect tense does not indicate frequency, but rather a single occurrence or a repeated action.•Present perfect continuous tense indicates an action that has been going on for a certain period of time, showing a sense of duration.3.Aspect:•Present perfect tense is used to focus on the result or the state of the action.•Present perfect continuous tense emphasizes the ongoing nature of the action.4.Time adverbs:•Present perfect tense is often accompanied by time adverbs like ever, never, just, already, yet, etc.•Present perfect continuous tense is often accompanied by time adverbs like for, since, and for + a period of time.5.Negative and interrogative forms:•The negative form of p resent perfect tense is formed by adding “not”after the main verb.•The negative form of present perfect continuous tense is formed by adding “not” before the verb “have” or “has” followed by the pastparticiple form of the main verb.Explanation: These differences highlight the nuances in using present perfect tense and present perfect continuous tense in English grammar. It is essential to understand these differences to use the correct tense in different contexts.六、书面表达题（15分）WritingSuppose you are going to visit a foreign friend, and you are making a travel plan. Write an email to your friend, including the following points:1.The destination and reasons for the visit.2.The dates and duration of the trip.3.The activities you plan to do during your visit.4.Any special requests or arrangements you need.You should write about 100 words on the ANSWER SHEET 2.Note: Do not use your real name in your writing. You may write your own address.Answer:Dear [Frien d’s Name],I hope this email finds you well. I am thrilled to hear that you’re going to visit us soon. I’ve made a travel plan for our visit, and I’d like to share it with you.We are planning to visit Paris, France. The main reasons for the visit are to explore the beautiful city and enjoy the rich culture there. The trip will last for two weeks, from July 15th to July 29th.During our visit, we plan to visit the Eiffel Tower, Louvre Museum, and Notre-Dame Cathedral. We also want to try some delicious French cuisine and enjoy a romantic evening by the Seine River.Best regards,[Your Name]Explanation:This writing task requires you to write an email to your friend, making a travel plan for your upcoming visit to Paris, France. The email should include the destination, reasons for the visit, dates and duration of the trip, and activities you plan to do during your visit. Additionally, you can mention any special requests or arrangements you need.The answer provided is a well-structured email that covers all the required points. It starts with a greeting and an expression of excitement to visit the friend. Then, it clearly states the destination (Paris, France) and the reasons for the visit. The dates and duration of the trip are mentioned, followed bythe activities planned. Finally, the email concludes with a request for any special requests or assistance, and a closing statement.The answer also maintains a friendly and polite tone throughout, which is appropriate for a personal email.。
北师大版三年级数学中考卷
北师大版三年级数学下册期中考试卷（2012~2013学年度第二学期）一、用心思考，正确填写（每空1分，共计33分）1. 在（）里填上“＞”“＜”或“=”。
8.00元（）8.0元 0.05元（）0.1元0.90元（）0.09元13×5 （）50 18×4（） 80 15×3（）13×5 40×70（）280 52×3（）520×0 650（）130×52. 4角5分＝（）元 23.30元＝（）元（）角6元 8分＝（）元 10.95元＝（）元（）角（）分3.连一连。
3×32 25×4 60×4 15×6---------------50×2 7×59 30×3 40×659×7 8×12 52×4 26×84. 在下面的（）里填上“平移”或“旋转”。
（1）拉抽屉的运动是（）现象；（2）开门时钥匙在锁孔中的运动先是（），然后是（）现象；（3）乘电梯从一楼到六楼电梯门的运动是（）现象；电梯是运动是（）现象。
5. 2013年的2月有（）天，有（）个星期零（）天。
6. 边长（）的正方形的面积就是1平方分米。
数学书封面的面积大约是5（）。
6. 5个140是（）；一个因数是49，另一个因数是5，积是（）。
7. 244的3倍是（）； 6乘108是（）。
二、仔细推敲，准确判断（每题1分，共计6分）1、23×18的积是三位数。
---------------------------（）2、 9乘0大于4成0。
---------------------------（）3、一张长方形的纸条上正好能够摆6个硬币，每个硬币的面积是2cm2，这张纸条的面积就是12cm2。
----------------------（）4、（1） 4 0 5 （2） 1 2 0 （3） 2 3 4× 4 × 5 × 91 8 0 0 6 0 02 0 7 6（）（）（）三、反复比较，谨慎选择（每题1分，共计5分）1、从镜子中看到的钟面是9时整，那么实际时间是（）时A、9 时B、3时C、15时D、3时或15时2. 14与最大的两位数相乘积是（）。
北师大版中考物理试卷及解答参考
北师大版物理中考复习试卷(答案在后面)一、单项选择题（本大题有10小题，每小题3分，共30分）1、关于声音的产生与传播，下列说法正确的是：A. 声音可以在真空中传播。
B. 声音是由物体振动产生的。
C. 声音在不同介质中的传播速度相同。
D. 只有固体才能传播声音。
2、关于光的现象，下列描述正确的是：A. 光从空气射入水中时，传播方向一定不变。
B. 当光线从一种介质进入另一种介质时，如果入射角大于临界角，则可能发生全反射现象。
C. 镜面反射遵守反射定律，而漫反射则不遵守。
D. 凸透镜对所有平行于主轴的光线都有会聚作用，不论光源位置如何。
3、在下列关于声音特性的说法中，正确的是：A、声音的频率越高，音调越低B、声音的响度越大，音调越高C、声音的频率越高，响度越小D、声音的响度与音调无关，只与振动幅度有关4、关于光的反射现象，以下说法正确的是：A、平面镜成像是由于光的折射形成的B、凹面镜成像是由于光的反射形成的C、凸透镜成像是由于光的反射形成的D、光在同种均匀介质中沿直线传播5、一个物体在水平地面上受到一个水平推力，以下关于这个物体运动状态的说法正确的是（）A、如果推力小于物体的最大静摩擦力，物体将保持静止状态。
B、如果推力等于物体的最大静摩擦力，物体将保持匀速直线运动状态。
C、如果推力大于物体的最大静摩擦力，物体将保持匀速直线运动状态。
D、如果推力等于物体的动摩擦力，物体将保持匀速直线运动状态。
6、一束光线从空气射入水中，以下关于折射现象的说法正确的是（）A、入射角小于折射角。
B、入射角等于折射角。
C、折射角大于入射角。
D、折射角与入射角之和等于90度。
7、在光滑水平面上，一个小球以速度(v1)与静止的另一个相同质量的小球发生弹性碰撞后，两球的速度分别为(v′1)和(v′2)。
如果碰撞前后系统的总动量保持不变，那么(v′1)和(v′2)的关系是？A.(v′1=v1),(v′2=0)B.(v′1=0),(v′2=v1)C.(v′1=−v1),(v′2=2v1)D.(v′1=12v1),(v′2=12v1)8、一个物体在做匀加速直线运动时，若其加速度逐渐增大，则物体的速度如何变化？A. 增加B. 减少C. 先增加后减少D. 保持不变9、题干：在下列哪种情况下，物体的机械能守恒？A. 物体在光滑水平面上受到恒力作用B. 物体在空中自由下落C. 物体在粗糙水平面上受到摩擦力作用D. 物体在斜面上匀速上升 10、题干：一个物体从静止开始沿着光滑水平面运动，下列关于其运动状态的描述正确的是：A. 物体做匀速直线运动B. 物体的速度逐渐减小C. 物体的加速度逐渐减小D. 物体的动能逐渐减小二、多项选择题（本大题有2小题，每小题3分，共6分）1、以下关于能量守恒定律的描述，正确的是（）A、能量既不能被创造，也不能被消灭，只能从一种形式转化为另一种形式B、在一个封闭系统中，能量总量保持不变C、能量守恒定律只适用于宏观物体，不适用于微观粒子D、能量转化过程中，转化效率总是达到100%2、关于力的作用效果，以下说法正确的是（）A、力的作用效果取决于力的大小B、力的作用效果取决于力的方向C、力的作用效果取决于力的作用点D、力的作用效果取决于力的性质E、力的作用效果与物体的质量无关三、填空题（本大题有5小题，每小题4分，共20分）1、当一个物体在水平面上做匀速直线运动时，如果该物体受到的摩擦力大小为5牛顿，则作用于该物体上的水平拉力大小应为______ 牛顿。
中考生物 专题三 生物与环境复习题 北师大版-北师大版初中九年级全册生物试题
专题三生物与环境课标细解读考点全突破一、生物的基本特征1．有生命的物体叫做生物，我们判断的依据是生物的特征，生物的特征主要有有应激性、生长、繁殖、新陈代谢。
二、生物与环境的关系1.在一定自然区域内，所有生物及其生活的环境共同构成生态系统。
地球上所有的生物及其生存环境构成了生物圈。
它可以进一步划分为陆地、湿地和海洋生态系统。
陆地生态系统可细分为荒漠、草原和森林生态系统。
荒漠生态系统可进一步划分为沙漠、盐碱、土荒漠生态系统等。
2．生态因素区分为非生物因素和生物因素。
非生物因素包括阳光、空气、水分、土壤、温度、湿度等多种因素。
生物因素指生物彼此之间的关系3.“朵朵葵花向太阳”体现了非生物因素中的光对生物的影响；“春江水暖鸭先知”体现了非生物因素中的温度对生物的影响；“螳螂捕蝉、黄雀在后”体现的生物因素对生物的影响；“大树底下好乘凉”体现了生物因素对非生物环境影响。
三、生态系统1.生态系统的组成成分有非生物的物质和能量、生产者、消费者和分解者等。
其中太阳能是所有生物生命活动的能量来源；绿色植物能够进行光合作用制造有机物，养活生物；稳定大气成分，所以属于生态系统中的生产者，动物能够直接或间接以绿色植物为食，帮助传播花粉、种子，所以属于生态系统中的消费者，各种细菌和真菌能够分解有机物成无机物，供给绿色植物再利用，所以属于生态系统中的分解者。
2.食物链和食物网是物质循环和能量流动的渠道。
生物富集是指生物从周围的环境中吸收并积累某种物质，使生物体内该物质的浓度不断增加的现象。
量流动和物质循环。
起点是绿色植物，单方向流动，且在传递过程中逐级递减，一个环节只能把所获能量的10%-20%传给下一环节，形成金字塔，这属于能量流动的特点。
物质在生物界与无机环境之间的往返循环是物质循环的特点。
自我调节能力。
自然因素和人为因素、外来物种入侵。
名师精解析【例1】2007年6月下旬以来，栖息在洞庭湖区400多万亩湖洲中的约20亿只东方田鼠随着水位上涨部分内迁。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
中考真题：先进的科学技术
（2015·湖北恩施）13．我国古代科技一直处于世界领先水平。
其中既然在发明过程中体现“变废为宝”的环保理念，又对文化的交流和保存提供了重要条件的科技成就是（）A．造纸术
B．印刷术
C．指南针
D．火药
（2015·山东泰安）3．关于秦汉科学技术成就的叙述，不正确的是（）
A．蔡伦发明了造纸术
B．《伤寒杂病论》阐述了中医的理论和治病原则
C．华佗制成了“麻沸散”
D．《九章算术》总结了春秋战国以来的数学成就
（2015·四川眉山）18．小明的爷爷是一位中医。
请你告诉小明华佗是什么时期的名医（）A．战国时期
B．秦朝时期
C．西汉时期
D．东汉时期
（2015·湖南怀化）30．东汉时期，蔡伦发明了造纸术，制成植物纤维纸。
（）×。