Why DC or AC Voltage?

Most recent answer: 07/29/2009

Q:
why we use dc supply in our electrical appliances instead of ac?
- arsalan (age 22)
pakistan
A:
Electrical items such as motors and heating elements can run very well on
alternating current (AC).  However most electronic items have transistors and these can be damaged by the opposite polarity voltage.  In addition an AC  voltage supply to the transistor would produce an annoying hum in the output response.  Many electronic systems can be run with an AC input, but this AC voltage is immediately rectified, filtered and converted into a DC voltage to power the internal components.

LeeH

(published on 07/29/2009)