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lovelyrwwr
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These are 2 stand alone problems, however the answers disagree with one another and I am trying to reconcile their differences. Any insight would be appreciated! :)
View attachment untitled2333.bmp
The answer is C. The answer provided with this question is that "there is no dependence on resistance of any kind".
However the question below seems to contradict this answer:
View attachment untitled23.bmp
View attachment untitled233.bmp
Following along the same logic as question 24, I assumed the answer was B. However the answer for problem 20 is supposedly D and the the following explanation was provided:
When switch 1 has been closed for a long time, the capacitor becomes fully charged and has a potential difference across the capacitor Vc that is equal to the potential difference V3.
Since the capacitor is fully charged, no more current should flow towards the capacitor, so the circuit can be thought of as having just R1 and R3.
View attachment 444.bmp
The equivalent resistance of R1 and R3 is the sum so Req = R1 + R3.EMF = I(Req)
I = EMF / Req
V3 = IR3 = (EMF/Req)R3
Taking V3 to equal the potential difference across the capacitor, we can find the charge on the capacitor:
Q=CV = CR3(EMF/R1+R2), which is answer D.I just don't see why the answer for problem 20 doesn't follow the same rule as problem 24. I expect that all capacitors - when fully charged - to have the same potential as the emf source. And that resistance does not affect the maximum amount of charge plates can hold as problem 23 suggests.
View attachment untitled2333.bmp
The answer is C. The answer provided with this question is that "there is no dependence on resistance of any kind".
However the question below seems to contradict this answer:
View attachment untitled23.bmp
View attachment untitled233.bmp
Following along the same logic as question 24, I assumed the answer was B. However the answer for problem 20 is supposedly D and the the following explanation was provided:
When switch 1 has been closed for a long time, the capacitor becomes fully charged and has a potential difference across the capacitor Vc that is equal to the potential difference V3.
Since the capacitor is fully charged, no more current should flow towards the capacitor, so the circuit can be thought of as having just R1 and R3.
View attachment 444.bmp
The equivalent resistance of R1 and R3 is the sum so Req = R1 + R3.EMF = I(Req)
I = EMF / Req
V3 = IR3 = (EMF/Req)R3
Taking V3 to equal the potential difference across the capacitor, we can find the charge on the capacitor:
Q=CV = CR3(EMF/R1+R2), which is answer D.I just don't see why the answer for problem 20 doesn't follow the same rule as problem 24. I expect that all capacitors - when fully charged - to have the same potential as the emf source. And that resistance does not affect the maximum amount of charge plates can hold as problem 23 suggests.
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