Need help with circuit problem

1. Sep 20, 2005

UnseenAngels07

the problem is a series combination of 12k resistor and an unknown capacitor is connected to a 13 volt battery. One second after the circuit is completed, the voltage across the capacitor is 8v. Determine the capacitance of the capacitor. :uhh:

2. Sep 21, 2005

mukundpa

This is the problem related of charging a capacitor.
The equation for the charge on the capacitor as a function of time is

$$\q = CV \left( 1 - e^\ -t/CR \right)$$