What is the difference between the Ac and The DC power system?
95388
dc is direct current. ac is alternating current.\nac current's voltage varies constantly in a sinusoidal manner, while DC has a constant, flat-line voltage
206602
In D.C circuits current flow is  always  in one direciton.\nIn A.C circuits current is fluctuating that is changing its direction periodically, say 50 times per second or 60 times per second. But in A.C when the current is switched off suddenly in some circuits having coils and condensers there will be back emf and sparks will be prduced in the switching system. Normally the device is manufactured taking this into account.
74815
no that is why our electricity is ran house to house in ac.  it is safer to operate ac and also more energy efficient.
415304
Electricity and magnetism are closely related.  When a current goes through a wire, it creates a magnetic field around the wire.  Similarly, if a magnetic field is moved past a wire, it can induce a current.\n\nA generator spins a magnet past a series of coiled wires, inducing currents in them.  Generators and alternators both work in this way.  The difference between the two is that in a generator, the current always goes in the same direction, while in an alternator, it switches directions due to the fact that the polarity of the magnet changes as it rotates.\n\nGenerators always produce Direct Current (DC current), while alternators always produce Alternating Current (AC current).\n\nThe difference in nuclear, steam, coal, oil and hydroelectric powerplants is simply in how the rotation of the generator is produced.  The generators work in exactly the same way in each case.\n\nSolar power is different.  In the case of solar power, the current can be generated in one of several different ways.  These are more complicated, however, and I don't know the specifics of how they work.  Sorry.
362045
markey watts = volts x amps , only for a Direct Current device. For AC, which we use in our wall outlets, there is another quantity called the power factor which is the cosine of the phase lag between the voltage and the current:\n\nwatts = volts x amps x powerfactor
787963
Actually no. I think there is about 5 volts DC. I guess the amount of power available depends on the computer, but it's probably very small. Maybe less that 500ma.
374690
DC is Direct Current in which the electrons move in one direction through the wire all the time.\nAC is Alternating Current in which the electrons flow one way for a short time and then switch directions and flow the other way for a while.\nThe constant direction switching does not interfere with the work the electricity does if the devices using it are properly designed. Some devices, like incandescent light bulbs, work equally well with either type of current. Other types of devices, like transformers, depend on the constant switching to operate.
46766
DC generator would have a rectifier built in to convert the AC to DC.
643695
From electricity...the term alternating current/direct current.
1172658
Actually it's a question in physics. I will try to explain it anyway:\nassume we have two windings w1 and w2 with  n1 rounds and n2 rounds respectively. If an A.C. voltage of V1 is connected to w1 then a voltage V2 will be induced in w2, satisfying the following equation:\nV1/V2=n1/n2 and for currents we have: I1/I2=n2/n1\nand it doesnt convert ac to dc to do so we should use a rectifier such as bridge rectifier etc
787904
generator.\n\nAn AC generator is turned by mechanical power like steam engine or a jet turbine. When its coils spin in a magnetic field, electricity is generated\n\n\nz
411263
AC or DC\n\nany phase differences\n\ndependent sources\n\nlinear or non linear elements\n\napplicability of theorems\n\nbilateral or not\n\nhomogeneity
873020
For a simple answer frequency applies only to alternating current.\n\nIf you want to get more technical then DC can have frequency if you use something like a thyristor (SCR) to produce stepped DC.  But this is used for simulating AC when you are using a load that requires AC and DC. An example of this would be  the control circuit for a reluctance motor.
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AC (alternating current) can be transformed into a DC (direct current) by means of a rectifier or bridge rectifier circuit depending on the AC circuit.\n\nA single AC line to ground or common an be rectified by the use of a single diode. This is a crude dc circuit.\n\nUsing a dual AC line, not grounded, where there are two lines, both above ground, then a full wave bridge rectifier can be used. Four diodes are used which rectify both the positive half as well as the negative half of the AC waveform.\n\nThen there is the 3phase rectifier bridge which uses 6 diodes, converting 3 AC lines, they are 120^deg outof phase of each other. Most industrial machines are using 3 phase power.\n\nMachines using this 3 phase power usually have a Motor Control Center which house a AC Drive (AC to DC to AC) inverter. This drive uses devices called IGBT which are active diode devices providing controlled amounts of power at variable frequency to run a machine.\n\nTo smooth out the DC waveform a capacitor bank is attached to the output of the DC bridge rectifier. \n\nAs you drive by an industrial park you will notice three power lines usually connected to each building. This is the 3 phase power. \n\nLarge Hybrid electric vehicles use such machines.
487275
Further reading of the reference given in answer 3 motivates this WARNING:\nA given AC current has greater biological/neurological effects than DC. 15 ma is enough to cause "Shock--painful, severe effects: muscular contractions, breathing difficulty". Also,"The threshold for a painful shock, in which muscles cannot let go, is 10.5 mA for AC current."\nJust in case this information inspires experimentation.
346869
In the US, current is set at 60 cycles and in Europe it is 50 cycles, that is the way it is made, I'm not sure you can change that after-the-fact, DC is of course direct.
80293
Batteries produce electricity, too. Probably what you mean is whether direct current (from batteries) or alternating current (from electric companies) is better...\n\nDirect current electricity is better than alternating current electricity...\n\nDirect current electricity produce more work with less energy than when using alternating current electricity...Although, availability of a.c. electrictiy is better than d.c. electricity.