[ 本帖最後由 chiharu 於 2006-9-8 00:35 編輯 ]作者: frizen20032003 時間: 2006-9-8 00:28 標題: 好型＠＠ 作者: chiharu 時間: 2006-9-8 00:38
thanks, 過獎啦．．．
而且我技術差到，在家中玩了半天，２個倒後鏡已斷予無數次．．．
令我唔想再黏返佢～作者: ryancmlam 時間: 2006-9-8 00:38
LED is a current driven device. What you need to do is to make sure the forward current is not too high. The typical forward current is aorund 20mA.
Assuming the forward voltage drop of a white LED is 3.2V, the voltage drop in the resistor that connected in series with the LED and voltage source (6V?) is 6-3.2=2.8V. The resistance of the series resistor should be 2.8V/20mA = 140 ohm.
If using a 100 ohm resistor, the current is around 2.8V/100ohm = 28mA. Still within the safety working limit. Should not be a problem.作者: chiharu 時間: 2006-9-8 00:46
very detail expanation. I think your subject of physic is very good!!
Even I was study art, I still understand, thank you very much~~~
I hope to bring my mini-z to football playground at night to play.....
of course less crash in big area...hahaha
