设计组装欧姆表实验探讨

Discussion on the Experiment of Designing and Assembling Ohmmeters

针对设计组装欧姆表实验作了深入探讨,分别对并联电路和串联电路进行了计算和分析,给出了实验中的元件的参数选择的具体计算公式和选择方法,并且发现,该实验中,在电池电压准确为1.5V的条件下,2种电路测量结果都比较准确;但是,在电压发生变化时,串联电路的测量值会出现很大的误差,最大可达30%,而并联电路测量值较为准确;电压在1.2～1.9V范围内变化时,相对误差一般小于0.5%.

This paper conducts in-depth discussion on the design and assembly of Ohmmeters, calculates the electric current and resistance in the series and parallel circuits, and presents the specific calculating formulas and selected methods for the choice of parameters of components in experiment. It is found that in this experiment, the circuit test results are very accurate under the condition that the battery voltage is accurately 1.5 v. However, with the change of voltage, the test value for the series circuits may vary significantly up to 30%, while the result for parallel circuit is relatively accurate. The relative difference is below 0.5% when the voltage varies between 1.2v tol. 9v.