because there is no transformer to step up or step down the dc voltage,and in the world most of the components are manufactured in the usage of ac only , that is the reasoning for usage of alternating current
This Website shows you what alternating currents are: http://www.play-hookey.com/ac_theory/
Thomas Edison believed it was dangerous to fool around with alternating currents and promoted the use of direct current instead. He was in a bitter rivalry with Nikola Tesla, who championed the use of alternating current for its efficiency over long distances.
Alternating Current
Alexander Russell has written: 'A treatise on the theory of alternating currents' -- subject(s): Accessible book, Alternating Electric currents
AC generators, powerplants etc produce alternating currents.
Knox McIlwain has written: 'High-frequency alternating currents' -- subject(s): Alternating Electric currents 'Principles of color television'
Edith Clarke has written: 'Circuit analysis of A-C power systems' -- subject(s): Alternating Electric currents, Alternating current, Electric circuits, Electric currents, Alternating, Electric power distribution
When you plug something into the wall socket at home, (mains power) you are using alternating current, when you use something powered by a battery, you are using direct current.
Direct current and alternating current
It is an alternating current that switches its polarity 60 times in a second. 60 Hertz is the frequency that electricity is generated in the U.S.
Abraham Press has written: 'Dynamo design' -- subject(s): Electric generators, Design and construction 'Treatment of harmonics in alternating current theory by means of a harmonic algebra' -- subject(s): Electric currents, Alternating, Alternating Electric currents
Harlan Morse Blake has written: 'Cases and materials on antitrust law' -- subject(s): Cases, Industrial Trusts, Restraint of trade