A 4.0 ?F capacitor is connected in series with a 2.0 k resistor across a 20-V DC
ID: 3898309 • Letter: A
Question
A 4.0 ?F capacitor is connected in series with a 2.0 k resistor across a 20-V DC source and an open switch. If the switch is closed at t = 0 s, what is the charge on the capacitor at t = 9 ms?PLEASE SHOW ALL WORK I KNOW THE ANSWER IS "68% of the maximum charge" BUT HOW DO YOU DERIVE THIS!!! I WILL ONLY AWARD POINT FOR CORRECT FORMULATION OF THE ANSWER! A 4.0 ?F capacitor is connected in series with a 2.0 k resistor across a 20-V DC source and an open switch. If the switch is closed at t = 0 s, what is the charge on the capacitor at t = 9 ms?
PLEASE SHOW ALL WORK I KNOW THE ANSWER IS "68% of the maximum charge" BUT HOW DO YOU DERIVE THIS!!! I WILL ONLY AWARD POINT FOR CORRECT FORMULATION OF THE ANSWER!
PLEASE SHOW ALL WORK I KNOW THE ANSWER IS "68% of the maximum charge" BUT HOW DO YOU DERIVE THIS!!! I WILL ONLY AWARD POINT FOR CORRECT FORMULATION OF THE ANSWER!
Explanation / Answer
voltage across capacitance will be
Vc = Vo(1- e^t/RC)
Vo = 20v , t = 9ms R = 2000 ohm C = 4.0 micro F
Vc = 20 (1-e^9ms/8ms) = 13.51 volts which is 67.54 %