Potential Difference Across Resistor (RC Circuit)?

AI Thread Summary
The discussion focuses on calculating the potential difference across a resistor in an RC circuit after closing the switch for 10 seconds. The provided equation, V = E (1 - e^(-t/RC)), is used to find the voltage, but the initial calculations yield an incorrect result of 4V. Participants express confusion over the expected behavior of the circuit, noting that after 10 seconds, the capacitor should be fully charged, resulting in zero voltage across the resistor. There is a consensus that the equation does not align with the physical behavior of the circuit in this scenario. The key takeaway is that the voltage across the resistor should indeed be zero after 10 seconds, contradicting the equation's prediction.
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Homework Statement



For the RC Circuit (R = 1M Ohm, C = 1 Micro Farad and E = 30 V) find the potential difference across the resistor 10 sec after the switch is closed.

Homework Equations



V = E (1 - e^ -t/RC)

The Attempt at a Solution



I use the above equation but I get it wrong (it should be 4V) I think I might be putting in something wrong.
 
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I think there is something wrong with your numbers and equation, because if the context is charging the capacitor with the resistor in series, the capacitor would be charged in 10 seconds, and the voltage across the resistor would have decreased to zero. But in your equation, the voltage (V) would approach 30V, so it doesn't make sense.
 
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