一小灯泡标有“6V 1.8W”字样,它正常工作时的电阻是        ;如

一小灯泡标有“6V 1.8W”字样,它正常工作时的电阻是        ;如果电阻保持不变,当加在它两端电压为5V时,通过它的电流为     。但是在它不工作时,用测电阻的仪表测得它的电阻却是8Ω。关于这种差异的合理解释是:金属的电阻随           而改变。

答案

20欧 0.25安 温度

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