咁我用梗new way本書啦, 講電既
electromagnetic induction個課就教到..
"methods to prevent sparks"
用電容並聯接駁開關, 系開關開路既時候, 個inductor既self-induced emf加埋個battrery既emf, 吾系大過電容既potential difference咩?
點解佢仲可以discharge到?我角得佢似系charging梗多啲bor:-s
或者個inductor五系即刻有自感電動勢, 咁電容就應該會放電.
但系咁佢地兩個既energy又flow左去邊到...好似吾太會conserve咁
有冇人明白我吾明啲咩? 我真系諗到頭刀爆, 本書成日刀有啲mistake, 搞到我刀五知邊啲岩邊啲錯.
(AL) methods to prevent sparks
2010-11-14 7:27 am
回答 (2)
2010-11-14 6:29 pm
✔ 最佳答案
How is the capacitor connected?Is it connected in parallel with the switch?
2010-11-14 10:29:24 補充：
If the capacitor is connected in parallel with the switch, it would be completely short-circuit when the switch is closed. Hence, there is no charge stored in the capacitor.
When the switch is suddenly opened, the induced back emf, which is ususally of high voltage, causes a spark to occur across the gap of the switch if no capacitor is connected.
If a capacitor is connected, then the energy from the induced back emf would flow to the capacitor, and this prevents the dissipation of energy by sparking.
2010-11-14 9:43 am
sure!! ---->用電容並聯接駁開關
收錄日期: 2021-04-29 17:37:34
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20101113000051KK01712