Electrical Engineering - Capacitors - Discussion
Discussion Forum : Capacitors - General Questions (Q.No. 2)
2.
A capacitor and a resistor are connected in series to a sine wave generator. The frequency is set so that the capacitive reactance is equal to the resistance and, thus, an equal amount of voltage appears across each component. If the frequency is increased
Discussion:
16 comments Page 1 of 2.
Vaibhav said:
1 decade ago
We know Xc=1/2pifcf, and if frequency increases then reactance decreases
and thus resistive voltage is greater than capacitive voltage or the frequency does not depend upon resistance hance resistive voltage unaffected by increase frequency while capacitive voltage decreases as initial by increase in frequency.
and thus resistive voltage is greater than capacitive voltage or the frequency does not depend upon resistance hance resistive voltage unaffected by increase frequency while capacitive voltage decreases as initial by increase in frequency.
Suresh said:
1 decade ago
Xc=1/(2pi.f.c) It shows that the reactance of capacitor is dependent about frequency.
If frequency increased then the reactance will be decreased.
But the resistanse is independent about frequency.
I hope you will understand.
If frequency increased then the reactance will be decreased.
But the resistanse is independent about frequency.
I hope you will understand.
Xyz mishra said:
1 decade ago
Vr>Vc. Because with increase in frequency the valie of xc decreases. As xc decreases so the potential drop also decreses. On the other paryt the vr remains the same as resistior is independent of frequency. So vc<vr.
Sayali sawant said:
1 decade ago
Capacitive reactance is inversely propotional to the frequency but resistance is independent from frequency. So resistance is more than capacitance. So answer is vr > vc.
(1)
Fazl hamad said:
1 decade ago
Dear fellows.
AS xc = 1/2 pi.f.c as f increases inversely xc decrease,
Also vc = i. xc as xc decreases so voltage across capacitor decreases.
Thus vr is greater than vc.
AS xc = 1/2 pi.f.c as f increases inversely xc decrease,
Also vc = i. xc as xc decreases so voltage across capacitor decreases.
Thus vr is greater than vc.
Mike said:
1 decade ago
Plain English. Capacitors allow a change in voltage to pass through. If it's allowing a higher frequency to pass through then the voltage drop on the capacitor lowers.
Priya said:
1 decade ago
Xc = 1/2πfc
Xc ∝ 1/f
As f increases , Xc decreases --> Vc decreases
But R is independent of frequency --> Vr remains the same.
Hence Vr > Vc
Xc ∝ 1/f
As f increases , Xc decreases --> Vc decreases
But R is independent of frequency --> Vr remains the same.
Hence Vr > Vc
AMARENDRA DASH said:
1 decade ago
From the ques Vr = Vc.
So IR = IXc.
Xc inver.proper to f,
As f increase Xc decrease resulting IXc decrease i.e Vc decrease.
Hence Vr > Vc. answer.
So IR = IXc.
Xc inver.proper to f,
As f increase Xc decrease resulting IXc decrease i.e Vc decrease.
Hence Vr > Vc. answer.
Siva naik said:
1 decade ago
if xc is increases then inversely frequency decreases.so that voltage across the capacitor is higher than that of voltage across the resistor
Selvaguru said:
8 years ago
Frequency and capacitive reactance value are inversely proportional to each other, when fc increased reduces the value of Xc hence VR >Vc.
(3)
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