Wikipedia:Reference desk/Archives/Science/2021 September 29

= September 29 =

Why does flow of current direction is matter if it doesn't effect final output readings?
I don't really understand the importance of direction of flow of charge, if output readings doesn't change whatever direction it flows? Rizosome (talk) 08:47, 29 September 2021 (UTC)
 * Whether it matters depends on what it is being used for. Incandescent bulbs work regardless of direction.  Diodes only let current flow one way, and LEDs will only give light if the current flows in that direction.  A DC motor will spin one way or the other depending on the direction of current.  Etc. Iapetus (talk) 09:04, 29 September 2021 (UTC)
 * If you don't care which electrode produces oxygen and which hydrogen, or which one gets covered with a new metal coat, then the direction actually doesn't matter. --CiaPan (talk) 12:22, 29 September 2021 (UTC)

In this line: LEDs will only give light if the current flows in that direction. What does "that" refer to? Rizosome (talk) 00:16, 30 September 2021 (UTC)
 * The direction that the diode allows, apparently. —Tamfang (talk) 01:19, 30 September 2021 (UTC)


 * In general, semiconductor components only work one-way. LEDs are made out of semiconductor components. One electrode is the anode, the other the cathode. To make them work properly with an AC feed, the current needs to be rectified. --Lambiam 06:51, 30 September 2021 (UTC)