测电源电动势和内电阻是高考电学实验的热点,采用伏安法测量是最基本的方法。但学生对这个实验的理解比较困惑。现在我谈一谈自己对这个实验的理解。一、实验原理本实验的原理是闭合电路欧姆定律。E=U+Ir,路端电压U和干路电流I是需要测量的物理量,所以选择电流表和伏特表。二、电路图由于之前已经学过伏安法测电阻,所以如果考虑电表内阻的 Measuring power electromotive force and internal resistance is the hottest college entrance examination, the use of voltammetry is the most basic method of measurement. But students are more puzzled by the understanding of this experiment. Now I will talk about my understanding of this experiment. First, the experimental principle The principle of this experiment is closed circuit Ohm’s law. E = U + Ir, road terminal voltage U and the trunk current I is the physical quantity that needs to be measured, so choose ammeter and voltmeter. Second, the circuit diagram Volt-ampere law as previously measured resistance, so if you consider the resistance of the meter