(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I have managed to calculate the first part of the question but the second part b I keep getting wrong. I was wondering whether you might give me some guidance. I am trying to find the current after 50s in part b below.

2. Relevant equations

time constant = RC

3. The attempt at a solution

a)Time constant = RC = (50 x 10-6 F) x (100, 000Ω)

Time constant = (5 x 10-5 F) x (100, 000Ω)

Time constant = 5sCorrect

b)T1/2 = 5 x In 2 = 3.4657...

50 seconds corresponds to 50/3.4657 = 14.41 half-times.

Δ changing current 14.41t1/2 = 90µA/2^14.41 = 4.13 x 10^-3 µA = 4.13 x 10^-6A

Current after 50 seconds is 4.13 x 10^-6A

This is wrong. Help. Thanks.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Finding Current after 50s Capacitors

**Physics Forums | Science Articles, Homework Help, Discussion**