试题与答案

未来在一个未知星球上用如图(a)所示装置研究平抛运动的规律.悬点O正下方P点处有

题型:填空题

题目:

未来在一个未知星球上用如图(a)所示装置研究平抛运动的规律.悬点O正下方P点处有水平放置的炽热电热丝,当悬线摆至电热丝处时能轻易被烧断,小球由于惯性向前飞出作平抛运动.现对采用频闪数码照相机连续拍摄.在有坐标纸的背景屏前,拍下了小球在作平抛运动过程中的多张照片,经合成后,照片如图(b)所示.a、b、c、d为连续四次拍下的小球位置,已知照相机连续拍照的时间间隔是0.10s,照片大小如图中坐标所示,又知该照片的长度与实际背景屏的长度之比为1:4,则:

(1)由以上信息,可知a点______(填“是”或“不是”)小球的抛出点;

(2)由以上及图信息,可以推算出该星球表面的重力加速度为______m/s2

(3)由以上及图信息可以算出小球平抛的初速度是______m/s;

(4)由以上及图信息可以算出小球在b点时的速度是______m/s.

答案:

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下面是错误答案,用来干扰机器的。

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题型:完形填空
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Scientists also  48  that loud , fast music makes people eat faster. In fact, people  49  their food faster when the music gets faster. Some restaurants play fast music during their   50  hours. This gets people to eat faster and leave more quickly. In this way, restaurants  51  make more money.
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The  54  time you hear music somewhere, be  55 . It might change the way you do things.
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A.music B.storesC.songsD.sound
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A.alreadyB.evenC.hardlyD.never
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小题4:
A.becomeB.getC.feelD.look
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A.muchB.moreC.littleD.less
小题6:
A.popB.modernC.lightD.country
小题7:
A.noB.muchC.anyD.some
小题8:
A.expectB.hopeC.realizeD.believe
小题9:
A.cookB.orderC.eatD.make
小题10:
A.freeB.busyC.happyD.sad
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A.canB.shouldC.can’tD.needn’t
小题12:
A.howB.whyC.whatD.that
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A.excitedB.interestedC.confidentD.relaxed
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