capacitive and inductive circuits

[PG1995]

Hi

Could you please help me with the query included in the attachment? Thanks a lot.

Regards
PG

 

[kubeek]

Impedance of a capacitor is Z=1/wC and I=V/Z (ohms law), so I=w.C.V
(applicable for steady state RMS voltage and current values)

 

[PG1995]

Thank you for the help, kubeek.

(applicable for steady state RMS voltage and current values)

I don't understand the quoted part. As you can see, in the attachment, I_0=ω*C*V_0, where "I_0" and "V_0" are peak current and voltage. I don't think they are RMS values, are they? So, could you please help me to see the relevance of your comment here? Thank you.

Regards
PG

 

[Ratchit]

PG1995,

Look at the equation above your question. Doesn't it say I=wCVo*cos(wt)?
So if I=Io*cos(wt), doesn't it stand to reason the Io=wCVo ?

Ratch

 

[kubeek]

Sorry, the RMS was superfluous, the numbers could be peak value, RMS or average. But anyway the ohms law equation I posted can be used only for amplitudes in steady state circuits, meaning you only have a single frequency involved and you look at the circuit after it has stabilized, that is after all transients from switching it on have diminished.

 

[PG1995]

PG1995,

Look at the equation above your question. Doesn't it say I=wCVo*cos(wt)?
So if I=Io*cos(wt), doesn't it stand to reason the Io=wCVo ?

Ratch

Hi Ratch

You have a point. Thanks for pointing this out.

Sorry, the RMS was superfluous, the numbers could be peak value, RMS or average. But anyway the ohms law equation I posted can be used only for amplitudes in steady state circuits, meaning you only have a single frequency involved and you look at the circuit after it has stabilized, that is after all transients from switching it on have diminished.

Thank you for clearing this out, kubeek.

Regards
PG

 

[lebevti]

Hi

Could you please help me with the query included in the attachment? Thanks a lot.

Regards
PG

i cant see at all, u need to blow it up

 

[vlad777]

With derivative of sin(wt), you need to use chain rule.
That's where that w comes from.