论文部分内容阅读
在测量小灯泡电阻的实验中,通过调节滑动变阻器使小灯泡两端的电压逐渐降低.多测几组电流和电压的数据,分别算出电阻,我们发现小灯泡的电阻逐渐变小了.八年级物理(人教版)《测量小灯泡的电阻》一节课后就提到了这样的问题:在测量小灯泡电阻的实验中,如果第一次测量时灯泡两端的电压等于灯口上的标定电压,以后几次测量时电压逐次降低,直到看不到灯泡发光.对比这样得出的几个电阻值,你能发现什么?尝试作出解释,然后设计实验证实(或否定)你的解释.
In the experiment of measuring the resistance of the small bulb, the voltage across the small bulb was gradually reduced by adjusting the sliding rheostat.According to the data of several groups of current and voltage, we calculated the resistance respectively and we found that the resistance of the small bulb became smaller gradually. (PEP) “Measuring the resistance of a small light bulb,” a class after the lesson mentioned the question: in the measurement of small bulb resistance experiment, if the first measurement of the voltage across the lamp bulb is equal to the nominal voltage on the lamp after After a few measurements, the voltage drops successively until no light bulb is visible. What can you find by comparing several of the resistance values so obtained? Try to explain and then design the experiment to confirm (or deny) your interpretation.