Post by deland $ [ [5 I5 _+ O7 e, d
大家都没说错,认为电阻不变的说的很对,如果你还用国内带来的灯泡的话,亮度只是原先的四分之一,这就太暗了,所以你要换这里的灯泡,认为功率不变的说的也很对,要达到原先的效果,就得换相同功率的灯泡,但导线内的电流加倍,不过不用担心,如果灯具以前在220V下没有危险的话,在110V下接相同功率的灯泡也没有危险,电压降为一半,电流加倍,导线上发热的功率还是与原先一样的.
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You are most right. But the last sentence is wrong. Here the power is ; J5 W8 O# I6 ?! h. M
8 ^ x. c% f$ t: ] pI**2*R, not 110V*I. 0 J- e" k0 ?7 a5 s) D2 }If you use the formula U*I, the U is the voltage difference between the two end points of the wire, it should be far less than 110V, otherwise the wire definately burns.8 F8 _+ Y% J9 x$ o
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导线上发热的功率 is 4 times.- t0 ^7 P& V; u$ W# l$ G7 s
/ M5 R5 T# }3 `, i4 k0 nTo be be simplest, buy a 40W local bulb (110V), and put it on. You will get 40W, and that is it. There is no problem for the wire except the wire is very very thin.