there is one question i need someone to help me to check and another question that i need someone to help with.(adsbygoogle = window.adsbygoogle || []).push({});

an alternationg voltage, V = Vosin (omega)(t) is applied across a pure capacitor of capacitance C.

derive an expression for the capacitive reactance.

i do it this way..

given V = Vosin (omega)(t)

but Q = CV

Q = CVosin (omega)(t)

I = dQ/dt

.

..

....

I = Io cos (omega)(t), where Io = CVo(omega)

capacitive reactance = Vo / Io

= 1 / C*(omega)

this is the only way to do it right?

the next question is

what is the effect on current in the circuit if the frequency of the power supply is increased, but its capacitance C of the capacitor and rms value of the alternating voltage V remain constant? without referring to the reactance of the circuit, explain your answer.

im not sure how to answer this question, and i dont answer for this question as well. what i can think of is... the value of the max current decreases because Io = CVo*omega

please correct me. thanks

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# AC Circuits in capacitor

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