光电效应法测量普朗克常数

Measurement of Planck Constant by Photoelectric Effect Method

在光电效应测量普朗克常数实验中,采用零电流法探究光源预热时间不同、光源与光电管距离不同、电压调节方向不同的情况对普朗克常数的影响。利用Origin软件对入射光频率v与截止电压Us的关系进行线性拟合,进而计算出普朗克常数。分析得到:光源预热25 min,光源与光电管距离为0.22 m,电压正向调节时为测量普朗克常数的最佳实验条件。

In the experiment to measure Planck Constant by Photoelectric Effect,the zero-current method was used to investi‐gate the effect of different preheating times of the light source,different distances between the light source and the photocell,and dif‐ferent directions of voltage regulation on Planck Constant.The relationship between the incident light frequency v and the cut-off voltage Us was linearly fitted using Origin software,and Planck Constant was calculated.The analysis showed that the best experi‐mental conditions for measuring Planck Constant were a preheating time of 25 minutes,a distance of 0.22 meters between the light source and the phototube,and positive voltage regulation.