advantages & disadvantages of ac to dc? dc to ac?

Answer 1

In the case of welding dc is better, but in the case of electric shock ac is better (if better can be used to describe electric shock) but not at heights.The reason is that dc shock causes your muscles to contract which means you grip whatever is giving you the shock and as you continue to be shocked you grip more. With ac because it is pulsing it causes your muscles to expand and contract which tends to throw off your hand/etc from whatever is shocking you. The problem with heights is when you get a shock and you're high up ac will cause you to be propelled backwards, usually away from safety and out into the wild blue yonder. I have had the miss fortune to witness this in real life when working in the steel erection industry.

Dave B

Answer 2

The big reason why ac is the source that powers our houses is that it can be generated at a power source such as a dam or a large poser plant and it can be transported hundreds if not thousands of miles.
dc would not be able to make it more than a few blocks at best.
There are two advantages for dc. The first is that a motor powered by dc can have variable speed. An ac motor is set at one speed. The only way it can change speeds is to switch windings.
The second advantage is that if it is in an area with combustible gas, it is not as much a hazard for starting a fire.

Answer 3

It is very hard to transform the voltage of DC. You have to convert it to AC first. It is much better to transmit electrical power at very high voltages, because the power in the wire = IV, but the heat dissipated in the wire = I^2R. This means it is important to kep I low, which you can do by keeping V high.

You can also transmit AC in 3 phases, that is as three separate waves on the same wires. If you keep the phases at 120 degrees to each other and balanced then there is no heat loss in the wires.

But if you want to export power to another grid system then DC is better. This is because all of the power stations on a power grid have to be in phase with each other. If they were not, the AC electric they tried to add to the grid would just cancel what was there. This is hard to arrange between different grids.

Answer 4

The advantage of AC for power transmission is indeed the fact that its voltage can be easily and efficiently raised and lowered using a transformer. And the fact that the power lost in the wire is proportional to the square of the current motivates you to minimize the current, therefore mazimize the voltage.

The only advantage of 3-phase AC is that when the voltage of one conductor crosses zero, you can still draw power from the other conductors.

Answer 5

I am looking at an AC pond.I have sticks stuck in the bottom of the pond,all over the pond.I toss a stone in to the pond.The variables would be stick diameter,stone size,stone force,wind on the surface of the pond,and so on.This would be an example of waves propagating to antennas.The energy is dissipated rather fast,but could be detected at all of the sticks.Now I have the same experiment with a DC pond.When I toss the stone there is a line of force that goes directly to one stick.All of the energy goes to the one stick.Sort of like being on the Internet.

Answer 6

Take a close look at the picture - look at the left side of the shaft. There is a brass-colored cylinder there, and there is a strip of metal in the front touching that cylinder, and a strip of metal in the back touching the other side of the cylinder. You can see two red-insulated wires leaving the rotor and one wire goes to one side of the cylinder and the other wire goes to the other side of the cylinder. The cylinder is not a single piece, it is cut along its length on opposite sides to form two pieces. This therefore splits the cylinder into two pieces. This makes the cylinder and the metal strips into a commutator. I have not been able to find any articles on the web that show a good explanation of how the commutator works. Wikipedia's article gives a little bit of information, but as there are other commutator designs, most of that article talks about those other designs. Other articles have poor drawings. It makes sense if you have the generator in front of you, as you can see the rotation changes the connection between the rotor wires and the rest of the circuit. You draw the circuit diagram yourself for one position of the rotor, then rotate the shaft 180 degrees and then draw the circuit diagram yourself for this second position of the rotor. By circuit diagram, I mean the electrical wiring and the magnetic fields, and label the direction of current flow in each diagram.

Answer 7

What kind of a stupid question is this ac and dc are just waveforms of an electric current.

Answer 8

ac travels further without losing current.
dc won't kill you like ac will, all electric chairs are ac