DC Supply-Current Status

DC = Direct Current. (and AC = Alternating Current.) So your question _{"If we are going to supply DC supply to that circuit, what about the current status?"} doesn't mean anything, does it ?

Yes.. You are correct.. The answer is definitely direct current...

If that circuit comprises of resistances as well as reactances, then

definitely the flow of current will be alternating current in nature even for

dc supply given.

For more understanding,

I = V/R..................> DC component current

I=v/Z.....................>AC component current (Z=R+jX)

Now, definitely the flow of current is Alternating Current in nature.

Please revisit your electrical fundamentals. If there is an inductance in the circuit and you apply Direct Voltage to it, the current in the inductance is STILL DC, and will rise as per the formula I = E/R * [1-e^(-R/L*t)] where 'L/R' is called the time-constant of the inductor. When the voltage is removed, the current again falls exponentially, as per the complementary formula. The current-rise and fall curve is something like this...

The current is NOT AC. It will rise to a value E/R and remain at that level. Similarly, if there is a capacitor in the circuit, its voltage will rise exponentially, and the current will reduce to zero. It is not AC

Thank you. Can you tell one thing,

For this circuit, the resultant AC current, will be whether pure AC or rippled DC ?

Thank you very much for your all nice response.

Your answer is accepted.

Thank you

You stated: "If that circuit comprises of resistances as well as reactances, then definitely the flow of current will be alternating current in nature even for dc supply given."

No.

Even in a circuit with reactive components undulating DC current is not ac. (Undulating means increasing and decreasing in this case. Not changing direction.)

One of the terminals of the DC input is the common reference point and there is no change in the direction of current during transitions from zero to the maximum level chosen and back to zero. Therefore there is no ac. Even changes in current direction inside the reactive circuit is not ac because it is always referenced to the common point of the power supply. Thus it is just an increase and decrease of a DC voltage or current.

The quality of the answers you get reflect the quality of your questions. For example, you did not established a Reference point and Test point for your circuit observations.

Kuduk

It is called (DC) Biased AC or DC Biased Wave.

How about dc bias by ac?

That is much too naive to try to address here. Sorry.

The decision tree has more branches than you can shake a stick at....

Please read Re:#3, then reply your comment

There might be some theoretical relevance to this, but I don't think it clarifies much. More likely the practical considerations about types of loads and control methods would be more important.

I apologize if this seems vague, but I believe you are overthinking "theory" without being familiar with some practical advantages of AC/DC versus each other.

Let us consider posting in CR4.

If we are going to post a question to CR4, what about putting some effort in effectively communicating a useful query?

I mean, whether it is a hypothetical question or a real-life scenario, why not post something interesting that isn't easier to just google, and why not provide a complete coherent explanation with all the necessary data?

If you think your question is worth taking time to read, justify it with the time you spend writing.

If your question is worthy of tapping into the knowledge at CR4, justify it by demonstrating in your original post that you have a sufficient basic grasp of the topic to understand/make use of the explanation that may be coming.

<...justify it...>

No.

Post the circuit diagram here using the camera button first.

Please give your answers.

I think the members missed out something.

There are certain conditions on which one would get an AC wave form super-imposed over the DC and in a special cases (with special elements) it would be undamped.

Now the questions of the OP smells of something so I won't elaborate it is for him to find out.

Going by the simple circuit given by him (#11), the complex situation you mention is not what he is meaning.

Come to that, if the components form an oscillator/chopper/inverter, the output will be AC.

RLC?

Well, he is mentioning R & L only. If he goes into resonance we can take it then

Well... Sir, i didn't mention that circuit as RL circuit.. I have mentioned that as load impedance i.e., Z = R+jX.

where,

Z= Impedance in ohm

X = Reactance (It includes Capacitive reactance as well as Inductive reactane, unless otherwise we specified)

Thank you...

So, my circuit has all. i.e., RLC. Now i thing definitely AC. Isn't it?

You and AP#1 can have a long, mutually satisfactory doscussion on this. It is beyond me.

Sir, i'm expecting answer for that. Please..

Oh no AP even when he wasn't AP never spoon fed. Only hints. That also was forced in this case.

Now OP - solve the differential equation of the RLC Circuit and find out.

Given your previous posts have you considered using the internet to look up basic electrical circuit theory FIRST rather than asking an online forum these questions?

It is also free, you will get more detailed answers and we won't have to answer basic questions that you really should be researching the answers to yourself.

Thank you for your reply..

I know to search in internet.. At the same time, we can realise more and more about any topic, when we start to discuss that particular topic.. Thats why, i posted.

If you cant, please dont disturb us who are all actively sharing their ideas according to subject.. Anyway, very thank you for your advice...

Thank you..

You already have your answer, see posts #13 and #25.

You may be confusing a DC step response for an AC waveform (perhaps because it is not constant and follows a mathematical decay response which you consider to be alternating, hence alternating current).

One last time, this type of simple (non-resonating) step response is not classified as AC (alternating current) because it does not periodically reverse direction regularly (for example the national power grid AC supply which operates at 50 or 60Hz and is considered AC).

"In alternating current (AC, also ac) the movement of electric charge periodically reverses direction. In direct current (DC, also dc), the flow of electric charge is only in one direction."

Link

If you apply dc to the circuit and there is never a change in the direction of the current as a reaction to the dc being applied then it is dc. A step further and you may consider the term undulating to the term dc if there is a variation in the current or voltage of the applied dc. As long as there is no change in the direction of the current there is no ac.