1.
(2023高二下·普宁月考)
智能手机中都配有气压传感器,传感器的电阻会随所处环境气压变化而变化。某实验小组在室温下用以下可供选择的器材探究:气压传感器的电阻值
随气压变化规律:
A.阻值随气压而变化的气压传感器一个(阻值变化范围从几十欧到几百欧);
B.直流电源,电动势6V,内阻不计;
C.电压表
, 量程为0~3V,内阻为3kΩ;
D.电压表
, 量程为0~15V,内阻为15kΩ;
E.电流表
, 量程为0~0.6A,内阻忽略不计;
F.电流表
, 量程为0~60mA,内阻忽略不计;
G.定值电阻
;
H.定值电阻
;
I.滑动变阻器R,最大电阻值约为50Ω;
J.开关与导线若干
![](//tikupic.21cnjy.com/2023/06/20/fe/03/fe0366875e1a3a73ba0b7185f7991873_316x180.png)
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(1)
小明设计了如图甲所示的实验电路原理图,其中电压表应选择,电流表应选择,定值电阻应选择。(选填实验器材代号)。
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(2)
当气压传感器所处环境压强为p时,闭合开关S,测得两个电表的读数分别为U=2.30V和I=23.0mA,则气压传感器阻值
![](//math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsub%3E%3Cmrow%3E%3Cmi%3ER%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmi%3Ex%3C%2Fmi%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3Cmo%3E%3D%3C%2Fmo%3E%3C%2Fmath%3E)
。(计算结果保留3位有效数字)
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(3)
当环境压强p改变时,测得不同的
![](//math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsub%3E%3Cmrow%3E%3Cmi%3ER%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmi%3Ex%3C%2Fmi%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3C%2Fmath%3E)
值,绘成图像如图丙所示,由图可得
![](//math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsub%3E%3Cmrow%3E%3Cmi%3ER%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmi%3Ex%3C%2Fmi%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3C%2Fmath%3E)
和压强p的关系表达式为
![](//math.21cnjy.com/MathMLToImage?mml=%3Cmath+xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F1998%2FMath%2FMathML%22%3E%3Cmsub%3E%3Cmrow%3E%3Cmi%3ER%3C%2Fmi%3E%3C%2Fmrow%3E%3Cmrow%3E%3Cmi%3Ex%3C%2Fmi%3E%3C%2Fmrow%3E%3C%2Fmsub%3E%3Cmo%3E%3D%3C%2Fmo%3E%3C%2Fmath%3E)
Ω。
![](//tikupic.21cnjy.com/2023/06/20/90/48/9048ebcdc9093f67409435fcc9e0a437_246x205.png)
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