10kW of electrical power is transmitted through a cable of resistance 1 ohm. Calculate the power loss when it is passed through the cable at
(a)220V
(b)400kV
F5 phy Electromagnetic Induction
2008-11-18 12:52 am
回答 (2)
2008-11-18 2:46 am
✔ 最佳答案
a. By P = IV10 000 = I(220)
Current, I = 45.45A
By Plost = I2R
= (45.45)2(1)
= 2.07 X 103 W
b. By P = IV
10 000 = I(400 000)
Current, I = 0.025A
By Plost = I2R
= (0.025)2(1)
= 6.25 X 10-4 W
That explains why electricity is transferred by high voltage in cable. It is to reduce the power lost.
參考: Myself~~~
2008-11-18 9:19 pm
嗯..想補充一下,我們常見的應該P=VI吧?(雖然P=IV都對,可是只是有點不慣)
**只是個人意見**
**只是個人意見**
收錄日期: 2021-04-24 10:42:54
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