Difference between AC and DC motors?
156772
So I don't think I saw an answer that I liked.  Motors move.  And the way motors move is with changing magnetic fields (electric current is changing with respect to time).\n\nWith AC motors, you have a changing current.  So you need to have a coil carrying the current, put it in a circle, and presto, you have a moving north pole moving around in a circle.  All you need is to have a magnet attached to a spindle, and the magnet will move around to follow the moving magnetic field rotating around in a circle.\n\nWith DC current it's different you do not have a changing current, but instead you have a steady current.  So how do you get the magnetic field to change?  You put a special device in that will flip the polarity of the voltage every half turn (or quarter turn depending on what you want).  So what happens is you get current flowing one way, and the magnet on the spindle moves to line up with the magnetic field, then on the spindel you have brushes which make contact with the DC voltage, as the spindle moves, the voltage is cut off, and then is reapplied, but now the voltage is reversed, and the north pole of the magnetic field is on the other side.  So the spindle moves, and the voltage is cut off, and then put back on and again reversed.  The DC motor as it moves reverses the voltage every half or quarter turn (depending on how you want to make it) so the motor creates the time varying magnetic field itself.
189249
totaly diferent motor
42027
you shouldn't have to rewire anything.  a(n AC) motor is a generator and a generator is a motor.  physically they are the same thing!  attach the motor contacts to a multimeter or oscilloscope, crank on that bad boy and watch what happens!
162542
AC has less loss over longer distance so is better for wide-area power distribution.  It is also better for high-voltage appliances with high amperage demands (like electric stoves, ovens, dryers, etc.).  Also, before the advent of reliable quartz crystals and such, AC provided a reliable timing source to synchronize signals for televisions (AC in U.S. operates as 60Hz) that is was much more difficult to obtain with DC.\n\nHowever, for local low-voltage, low-amperage power DC is more efficient as most of the types of devices that fit into this category cannot utilize AC directly - they need to convert AC to DC.  It would be more efficient to have a single DC power source using step-down transformers to adjust voltage, than have a bunch of separte AC/DC converters.\n\nIncandescent light bulbs don't care which type of current they are powered from (although LED's do).
699817
DC means that you have a constant voltage.  A battery is a great example of DC.  I used to like to think of electricity as water- voltage is how high up the water tank is (the higher up it is, the harder it pushes the water down), resistance is how thick the downpipe is, and current is the volume of water that flows down.  All three are connected, eg a narrower pipe gives less current \n\nAC is as if your source pushes, then pulls, then pushes, etc, the electricity.  This is what you get in your power socket.  It looks a bit like a kid jumping up and down on a trampoline... he pushes as he hits the trampoline, and pulls as he flies up.  To use our water example: imagine a pump that pushes the water, then sucks it back, then pushes...\n\nNo idea how this relates to Venn diagrams, sorry
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
721433
Edit: Perhaps I should revamp my answer to provide a clearer (actual) answer, that explains exactly what plays a role and, in effect, why I am right. I also added a couple sources you should read (in case you don't believe me ;-).\n\nAs asked at the first source (which has very good information about electric motors), "How can I make the motor spin faster or slower?". The answer is that it has to do with the power of the magnetic field. Because electicity is magnetic, you can either effect the speed by using a more powerful magnet or a more powerfully magnetic electrical current.\n\nTo quote Wikipedia about what a volt is, "The volt is the SI derived unit of electric potential difference". To truly understand what the "electric potential difference" means, you must first better understand the volt. The volt is a measurement of electromotive force (emf) and is just defined in terms of amperes and watts.\n\nAn amp is the constant current which produces a force equal to 2x10^-7N per meter, when travelling across two parellel wires one meter apart. It is one coulomb of charge per second (Q/t). It is a base unit upon which other units of electicity are defined (such as the volt).\nA watt is the unit of power equal to one joule of energy per second (P=W/t).\n\nHmm. Power? Power of a magnetic field? So how can you get more power in your circuit? If your power source is not rated by power output, then you can figure out the power using convertion:\nA=W/V=C/s\n\nIf you want a higher wattage, you can increase the voltage (electrical potential) or the ampage (current) or both. Or you can increase the charge - the amount of electricity (coulombs).\n\nSo the fact remains that voltage is *not* directly related to the speed of a motor. It can be directly converted in a way that makes it useful for that purpose, but any number of other things can be done to increase the power - the real goal you are looking for.\n\nThe answer is a definite "No." and a half-assed "Yes.".\n\n\n---Original Answer---\nNo. You might want to read more about the electric motor ( http://en.wikipedia.org/wiki/Electric_motor ) and magnetic properties of electricity ( http://en.wikipedia.org/wiki/Electromagnetism ). Also see the definitions of volt ( http://en.wikipedia.org/wiki/Volt ), watt ( http://en.wikipedia.org/wiki/Watt ), and amp ( http://en.wikipedia.org/wiki/Ampere ).
591697
I don't know the exact definition, but they differ on the way they deliver energy.\nDC generators give electricity at a given steady voltage, but AC generators give electricity in an continuous alternating voltage.
831663
Variable voltage and frequency drives operate by first converting the incoming ac (typically 50 or 60Hz) into dc.  Then the drive controller uses this DC to generate an AC output that has the proper frequency to turn the motor at the desired speed.  The voltage output is varied depending on the amount of load on the motor.
108567
Simply put A.C. is easy to transform, from one voltage to another, with relatively little loss. Higher voltages are used for long distances, for example the common wooden power poles are 10,000-80,000V but houshould Power in U.S. is only 120/240V (Probably between 100-300V? in India)
455913
DC (direct current) only flows in one direction.  AC (alternating current) is current which changes direction back and forth with a regular period.\n   The electrons really do flow.  If you look at the "drift", or physical motion of an individual electron, it is much slower than you might think.  In a 12-gauge copper wire carrying 20 Amps of current, the average speed of an electron is quite slow; about 1/250 of a mile per hour.  There's just so many electrons moving along so slowly that it adds up to a substantial current.\n   Why then, when you flip a switch, does the light turn on so quickly?  That's due to wave propagation, which is much faster.  Think of waves in the deep ocean; the waves can move quite quickly, but if you're swimming in it, you're not moving nearly so quickly.  You feel a slight up and down motion, but the wave may be propagating at 30 MPH.  The water itself is not flowing along across the surface at 30 MPH, but the wave is.\n    It is exactly the same with electrons.  While the wave is moving very quickly, the electrons themselves move very little.  In the wiring of your house carrying 20 Amps of AC current, the electrons are wiggling back and forth 60 times per second over a distance of about one thousandth of an inch.\n    However, the wave moves much much faster, when you flip the switch, the change in voltage travels along the wiring at very near the speed of light (it's slowed down about 30% below the speed of light by the plastic insulation on the wire).\n    With that prelude, to answer your questions:\n- the copper wire is not typically called an ion.  During current flow, an atom may hand its extra electron to the next copper atom, but it also gets an electron from the atom on the other side.  Thus, each atom always stays about neutral in charge.  This is described as the copper atoms forming a lattice through which the "sea" of electrons can freely flow.\n- a heater does not work by converting kinetic energy of electrons to heat quite the way you describe.  Instead, it uses the electrical energy available on the conductors of the power cord, which takes the form of electrostatic force of attraction which pushes electrons from the negative line to the positive line.  As an electron eneters the heating element from the negative line, it feels a strong force of attraction towards the other end of the heating element, which is connected to the positive line.  The electron accelerates due to this force, and speeds up somewhat, but it travels only a fraction of a millimeter before it collides with a microscopic defect in the lattice of the heating element, and decelerates and transfers its kinetic energy into vibration of the lattice of atoms of the heating element (i.e. into heat).  It then accelerates again, then hits another defect.\n   The main thing which distinguishes the metal of the heating element from the metal of the copper wires feeding them is that the heating element has a higher density of lattice defects (i.e. higher resistance).  An excellent analogy is American falls at Niagra, where the water approaches in a deep, broad stream moving relatively slowly at high potential (i.e. the negative copper wire), then tumbles down quickly under acceleration of gravity, losing potential, but hitting a bunch of rocks on the way down.  Hitting each rock slows the water down, and also transfers some heat to the rock, but after each impact the water accelerates again as it falls to the next rock.  Then, the water leaves at lower potential in another slow, deep stream (i.e. the positive copper wire).
167412
My suggestion would be to use a d.c. motor .  Incorporate the following : A D.C. motor, 2 momentary contact up/down switch, a reversing relay that would switch positive and negative when switching from up to down . Associated micro switches and ice cube relays to sense position and stop motor when destination is reached. Some form of safety clutch,light curtain etc. And a rectifier to convert house hold alternating current to D.C. . An alternative would be a reversing A.C. motor and associated similar controls less rectifier. Similar installation difficulty , my decision a/c vs d/c would be based on price and availability.
87071
Probably pretty close to the same, the main factor that reduces a motor's speed is bearing friction, it would be slightly faster, because there would be no friction on the armature caused by air movement. If it is a D.C. motor (particularly a series field), the speed variations would be higher than for a fixed speed A.C. motor, and the speed of a syncroonous A.C. motor would be unnafected, however its current consumption would probably be slightly reduced. Also, the tourqe for almost any electric motor would be affected by the temperature change (lower temp. = more tourqe = higher current consumption), and possibly, this could affect speed.
122327
ELECTRICITY FLOWS IN TWO WAYS, AC & DC.\n\nAC flows alternatively (back and forth between + and -)\n\nDC flows directly (across + and -)
40896
Both answers above are correct:\nIn physics, AC/DC is alternating current, direct current.\nIn slang, it means "goes both ways" i.e. bisexual\nIn rock n' roll, it means a kick ass band!
479271
AC Stands for Alternating current, which is a Wave that carries the current in Frequency Cycles, In the U.S. We use 60Hz or 60 cycles, In Europe/Canada/South America it is 50Hz.  Alternating Current comes in Single, to 3 phases, which are 3 currents carried in the same medium.  Direct Current is a Straight current carried in single form.  Less manageable than AC but much more deadly as it can carry large amounts of Amperage(Speed of the electrons creating heat).  Hope this helped you.
240273
The terms are sometimes all used interchangeably.  An engine is any device that produces a useful effect, a crowbar is the engine of choice to move a rock, etc.  Your mind is the engine that could creat a best-selling novel, or engineer a bank heist (I hate the way engineer is used sometimes!).  Therefore the gas-burning motor in a motorcar is the engine that drives it.\n\nIn the field of electric power, motors use electricity to create motion (there are linear and rotary motors) and generators use motion to create electricity (there are linear and rotary generators).  There are also motor-generator sets, for example where an AC motor drives a DC generator (or the reverse).  There are also reversible units such that when driven they act like generators and supply electricity but when supplied with electricity they act as motors.\n\nThe bottom line is that when you use the terms motor, generator or engine you must make it clear which you are discussing unless it is clear in context (my engine overheated?).