Need help with voltage across a capacitor in a DC circuit

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Discussion Overview

The discussion revolves around the behavior of voltage across a capacitor in a DC circuit, particularly in the context of an RC circuit. Participants explore the implications of current direction on voltage polarity and the conditions under which current flows through the capacitor.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether the voltage across a capacitor is always considered negative regardless of the current direction when setting up a voltage equation.
  • Another participant asserts that when traveling with the current, the voltage is negative (indicating a voltage drop), while against it, the voltage is positive.
  • There is a clarification about the circuit type, confirming it is a DC circuit, with a note that AC will be discussed later.
  • One participant states that current flows only while the capacitor is charging.
  • Another participant counters that current can also flow when the capacitor is discharging.
  • A later reply suggests that the original question could be clearer with accompanying schematics.

Areas of Agreement / Disagreement

Participants express differing views on the behavior of voltage across the capacitor and the conditions for current flow, indicating that multiple competing perspectives remain without consensus.

Contextual Notes

There are unresolved aspects regarding the definitions of voltage polarity and current flow in the context of charging and discharging capacitors, as well as the implications of current direction on voltage measurements.

Blockade
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In a RC circuit is voltage through a capacitor always consider negative no matter if you're going with or against the current when setting up a voltage equation?
 
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Short answer no.

Travelling with the current the voltage is negative (eg a Voltage drop). Against it, positive.
 
PS is this a DC or AC circuit?
 
CWatters said:
PS is this a DC or AC circuit?
It's a DC. We will not be covering AC until a couple more weeks.
 
Ok in which case there is only current flowing while the capacitor is charging.
 
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My understanding is current could also flow when the capacitor is discharging.
 
oops yes that as well.
 
Blockade said:
In a RC circuit is voltage through a capacitor always consider negative no matter if you're going with or against the current when setting up a voltage equation?
I don't know what you mean by the wording of your question. It would be better if you came up with some schematics on which you can base your question.
 

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