The net result is that a 5% reduction in the voltage more than doubles the life of the bulb, but delivers 20% less light.
综上所述，减少电压5%能使灯泡的使用寿命延长至少2倍，但是其亮度会下降20%。
Just like with your flashlight that you have at home, you sometimes have to put in several cells in series to get a higher voltage so that you can power a small light bulb.
就像你家里的，手电筒，你有时必须，放几个电池，来达到一个更高的电压，以此点亮一个小灯泡。
What is the ratio between the thermal energy and light energy emitted from a small electric bulb depending on the voltage applied to a bulb?
一个小灯泡发出的热能和光能的比例是怎样由给小灯泡的电压所决定的？
应用推荐