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2016年全国高考新课标卷Ⅰ理综(物理)23题为电学实验题。原题:现要组装一个由热敏电阻控制的报警系统,要求当热敏电阻的温度达到或超过60℃时,系统报警。提供的器材有:热敏电阻,报警器(内阻很小,流过的电流超过Ic时就会报警),电阻箱(最大阻值为999.9Ω),直流电源(输出电压为U,内阻不计),滑动变阻器R(1最大阻值为1000Ω),滑动变阻器R(2最大阻值为2000Ω),单刀双掷开关一个,导线若干。在室温下对系统进行调节。已知U约为
2016 national college entrance examination new curricula Volume I rationale (Physics) 23 entitled electrical experiment questions. The original question: To assemble a thermistor-controlled alarm system, the system requires the alarm when the temperature of the thermistor reaches or exceeds 60 ° C. Equipment provided are: thermistor, alarm (resistance is small, the current will flow over the Ic will alarm), resistance box (maximum resistance 999.9Ω), DC power supply (output voltage U, internal resistance Excluding), sliding rheostat R (1 maximum resistance of 1000Ω), sliding rheostat R (2 maximum resistance of 2000Ω), single-pole double-throw switch, a number of wires. The system is conditioned at room temperature. U known to be about