电位差计实验仪器匹配与控制电路的设计思考

设计性实验是当前大学物理实验教学改革中出现的一种新的实验类型,其教学形式、内容和要求目前还处于不断试验、充实、发展和完善之中。针对学生在设计过程中选配仪器上出现的不足,从开设电位差计实验出发,讨论了电位差与检流计的匹配关系,提出当检流计的内阻与电位差计内阻相接近,同时又符合检流计接近工作在临界状态的条件下,电位差的测量灵敏度为最高。并以"用电位差计校验毫安表"实验为例,在兼顾实验室现有实验设备的基础上,提出控制电路的设计思路,使其既能满足实验要求,又能安全省电。

The Design of the Experiment Instrument Matching of Potentiometer and its Control Circuit

With the development of current university physics experiment the designing-oriented experiment is new in the lab experiment. However,its pattern,content and requirement still need be improved. Aiming at the analysis of the deficiency of experiment instruments,the paper discusses the method of matching the potentiometer and the galvanometer. The result shows that the maximum sensitivity of the potentiometer can be achieved when setting the inner resistance of potentiometer and the galvanometer similar with the galvanometer working under the critical state. The paper also cites the experiment--"Verifying the milli-ammeter with potentiometer" to illustrate how to design the control circuit of the potentiometer experiment at the request of the experiment based on the current circuit.