Register to reply 
Time required to charge a capacitor 
Share this thread: 
#1
Oct709, 09:22 PM

P: 69

1. The problem statement, all variables and given/known data
A capacitor with a capacitance of C = 28.7 μF is slowly charged by a constant current of I = 63.2 nA. How long does it take to charge the capacitor to a voltage of V = 28.9 V? 2. Relevant equations q=cvb(1e^(t/RC)) Vb=IR+QC 3. The attempt at a solution I have tried to solve for R by R=I/V but I don't know how to solve for t because Q is not given, and I don't know how to find it. Any ideas? I only got a couple hours left. Any help is greatly appreciated. 


#2
Oct709, 09:38 PM

HW Helper
PF Gold
P: 3,440

The statement that the current is constant says that you are in the linear region all the way to charging the capacitor to 28.9 V. You can calculate how much charge is on the plates when the voltage is 28.9 V and from this the time it takes for this charge to accumulate at a constant rate. The exponential is not needed here.



Register to reply 
Related Discussions  
Time Constant / Capacitor Charge Time  Introductory Physics Homework  19  
Work required to move charge  Introductory Physics Homework  4  
Work required to move the charge  Introductory Physics Homework  1  
The work required for adding a charge to an infinite charge distribution  Advanced Physics Homework  1  
A Problem regarding Charge density, some Calc mar by required  Introductory Physics Homework  1 