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问题 问答题 简答题

如果只知道帽子的高度，而不知道帽子的宽度，在制图时，如果定帽宽的尺寸？

答案

参考答案：如果只知道帽子的高度。而没有帽子的宽度，制图时可以用二分之一领围+2.5CM来定帽子的宽度，但前中位要挖进3-5CM露脸的位置。

实验题

热敏电阻的阻值会随温度的改变而改变。小明同学用甲图所示的电路来探究热敏电阻RT的阻值与温度的关系。已知M为控温器，电源电压恒为12伏，R为电阻箱。

（1）在控温器中应该加入下列哪种液体？        

A．自来水   B．煤油  C．食盐溶液 

（2）当控温器中液体温度为80℃，电阻箱阻值为100欧时，电流表的示数为0.1安。则

该温度下热敏电阻的阻值为        欧。

（3）依次改变控温器中的液体温度，同时改变电阻箱的阻值，使电流表的示数始终保持

在0.1安。通过计算得到相关数据记录如下。从表中可以看出，在一定温度范围内，该

热敏电阻的阻值随温度的升高而         。

温度t（℃）70605040302010…
电阻RT（欧）22283544567394…
 

（4）在科技创新活动中，小春用该热敏电阻和电压表制成了 一支指针式温度计（如图乙）。它可以直接在电压表刻度  盘上读出相应温度。若电压表的读数会随温度的升高而增大，则应在原理图（乙）中             两端接入一个电压表。（填“ab 、 bc 或 ac”）
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改错题

第二节：短文改错（共10小题：每小题1.5分，满分15分）

Mr.Turner turned over in bed from time to time in last

night, for he was very excited to fall asleep. Yesterday morning, he   76__________

went to a big gardening company, knowing as Green fingers, for     77__________

a interview. Mr Turner, who liked to help his grandfather grow      78__________

flowers in the garden, looking forward to the job. When he got      79__________

to the company, he found there were so many people waiting       80__________

there that he had no ideas whether he could get the job. While       81__________

waited, he helped the workers there to remove the fallen trees      82__________

and clear the road. Unluckily, he was the only one who finally      83__________

got the job, so the manager decided to give the job to whoever he    84 __________

believed was helpful.                                       85 __________
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