# Initial voltage of capacitor

1. May 8, 2017

### Abdulwahab Hajar

1. The problem statement, all variables and given/known data
I would like to know the initial voltage across the capacitor terminals in the following diagram.

2. Relevant equations
when a capacitor is connected to a DC source for a long time, it acts an open circuit.

3. The attempt at a solution
for t < 0, we get the diagram below and I believe the voltage should be 12V right?
just making sure, cuz In an online solution it said the voltage is 0, if so why?
Thank you

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2. May 8, 2017

### Staff: Mentor

Before t = 0 the circuit is open at b. How could charge flow into the capacitor?

3. May 8, 2017

### Abdulwahab Hajar

but isn't one of the terminals of the capacitor connected to the 12V source?
while the other is just simply disconnected.... shouldn't that incur a potential difference between the two plates

4. May 8, 2017

### Abdulwahab Hajar

never mind sir, I get it..... very silly mistake
thanks though