Answer / poonam

AC voltage is alternating voltage having frequency of 50Hz.
(60 Hz in US)
It has positive peak and negative peak value.
DC is direct voltage having 0 frequency and maintains
constant level.

Answer / suthan prabhu

In a 50Hz A.C system , Voltage will cross 50 times zero.
But in Dc there is no Zero crossing.

Answer / amirtha

ac voltage have both +ve and -ve peaks... but the dc
voltage is constant it is maintained at particular
level...but in ac.. it increases and reaches peak value and
become zero and negative peak.....

Answer / nagarjuna

AC VOLTAGES HAVE +VE AND -VE PEAKS.
AC VOLTAGES WIL HAVE FREQUENCIES.
DC VOLTAGES DNT HAVE AMPLITUDE.
DC VOLTAGES DNT HAVE ANY FREQUENCIES.

Answer / ramesh

AC voltage has frequency, but in DC voltage there will be zero frequency.

Ac voltage will have phase and neutral.
DC Voltage have +ve and -ve.

in AC Voltage eg 230 Volts. Phase to earth will have 230 Volts and Neutral to earth should be less than 5 volts.

But in DC eg 220 Volts. +ve to Earth will be +110Volts and -VE to Earth will be -110 Volts.


Relation between AC and DC Voltage is
AC volt * 1.414 = DC Volt

Answer / priti

Direct current or DC electric motors work for situations where speed needs to be controlled. DC motors have a stable and continuous current. DC motors were the first and earliest motors used. They were found, however, to not be as good at producing power over long lengths. Electric companies found using DC motors to generate electric did not work because the power was lost as the electric was transmitted. Brush DC motors use rings that conduct the current and form the magnetic drive that powers the rotor. Brushless DC motors use a switch to produce the magnetic drive that powers the rotor. Direct current motors are often found in appliances around the home.
Alternating current or AC electric motors are used differently based on what type of AC motor it is. Single phase AC motors are known as general purpose motors. They work well in many different situations. These AC motors work great for systems that are hard to start because they need a lot of power up front. Three phase, also called polyphase, AC motors are usually found in industrial settings. These motors also have high starting power built transmit lower levels of overall power. AC power gets its name from the fact that it alternates in power. The amount of power given off by an AC motor is determined by the amount of power needed to operate the system.

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