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voltage across capacitor

bhuvanesh

Aug 29, 2013
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i dont know how voltage across r1 is equal to voltage across c since c and r2 are in series
 

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LvW

Apr 12, 2014
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R1 is in parallel to the voltage source. Thus, the voltage across r1 is identical to the source voltage V1 (12 V).
The voltage across C1 is nearly identical to the source voltage due its very large parallel loss resistance - in parallel with the instrument´s input resistance..
 
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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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What current flows through R2?

Therefore, what is the voltage drop across R2?

Therefore what is the voltage across C1?

Consider the steady state condition after the circuit has been left sitting like this for some time...
 

bhuvanesh

Aug 29, 2013
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What current flows through R2?

Therefore, what is the voltage drop across R2?

Therefore what is the voltage across C1?

Consider the steady state condition after the circuit has been left sitting like this for some time...

what i want to know is.doesnt R2 contribute any voltage drop.
 

dcac

Jul 10, 2013
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what i want to know is.doesnt R2 contribute any voltage drop.

R2 does contrribute to the the voltage across the capacitor. However, R2 is responsible for the time that takes to charge up to the voltage.
 

bhuvanesh

Aug 29, 2013
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R2 does contrribute to the the voltage across the capacitor. However, R2 is responsible for the time that takes to charge up to the voltage.

why R2 doesnt contribute any voltage.why?

capacitor blocks dc current since the R2 is in series with capacitor.it does allow any current to pass through so no voltage drop across R2. am i right
 

Harald Kapp

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Take heed of Stev's advice:
Consider the steady state condition after the circuit has been left sitting like this for some time...

Conversely: look at the voltage across R2 when you turn on V1 initially (after C1 has been discharged). Here is a lesson that explains the effect.
 

bhuvanesh

Aug 29, 2013
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Take heed of Stev's advice:


Conversely: look at the voltage across R2 when you turn on V1 initially (after C1 has been discharged). Here is a lesson that explains the effect.
thanks for the ppt.i am stating what i read from that ppt.correct me if i am wrong
1)till the capacitor being fully charged there is some flow of current through R2.
2)charging and discharging upto time constant is only depends on R and C,whereas the transient period and steady state are not
sorry if i am wrong
 

Harald Kapp

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1 is o.k.
2:
whereas the transient period and steady state are not
Charging and discharging is the transient period. Therefore only the voltage in steady stae is independent from R and C, the voltage during the transient time is dependent on R and C.
 

bhuvanesh

Aug 29, 2013
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1 is o.k.
2: Charging and discharging is the transient period. Therefore only the voltage in steady stae is independent from R and C, the voltage during the transient time is dependent on R and C.
thank you so much.i am clear.do u any one know is there something like chating to get instant answer than rather placing it in forum and waiting for a while.
 
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