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Charging and discharging capacitors  current time graph 
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#1
Apr312, 08:23 AM

P: 614

1. The problem statement, all variables and given/known data
why is the currenttime graph for a charging AND discharging capacitor the same? 2. Relevant equations 3. The attempt at a solution Q=It so for a discharging capacitor as time goes on the charge stored decreases so current decreases BUT for a charging capacitor charge increases so current should increase?? 


#2
Apr312, 09:32 AM

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Think in terms of the potential difference that is driving the current. How much of the potential appears across the resistor over time?



#3
Apr312, 11:42 AM

P: 614




#4
Apr312, 11:46 AM

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Charging and discharging capacitors  current time graph



#5
Apr312, 12:52 PM

P: 614

I think so...



#6
Apr312, 01:05 PM

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P: 11,683

Sketch the PD across the capacitor for the charging case. You should be able to infer the PD across the resistor using KVL for the circuit (battery, resistor, capacitor). What do you find?



#7
Apr312, 01:09 PM

P: 614




#8
Apr312, 01:46 PM

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#9
Apr312, 03:11 PM

P: 614

no idea about resistor, sorry :( 


#10
Apr312, 03:19 PM

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#11
Apr312, 04:18 PM

P: 614

V = V_{1} + V_{2}
so I would presume the emf across the resistor falls as p.d across capacitor increases (and then increases as p.d across capacitor decreases) 


#12
Apr312, 04:39 PM

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#13
Apr312, 04:43 PM

P: 614

it is only involved during discharging surely your approach is wrong? 


#14
Apr312, 04:49 PM

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#15
Apr312, 04:56 PM

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#16
Apr312, 05:30 PM

P: 614




#17
Apr312, 05:40 PM

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#18
Apr312, 05:53 PM

P: 614




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