- #1
etown
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Homework Statement
The switch in the figure has been in position a for a long time. It is changed to position "b" at t=0s. What is the charge Q on the capacitor at t=50s?
(zeros denote empty space in the circuit)
|----(a)0000(b)--------- |
|00000\00000000000000|
9V00000\000000000000|
|00000000|00000000025 Ohm
|00000004uF000000000|
|________|___________|
Homework Equations
(1) C=Q/V
(2) V=IR
(3) q=Qinit.(1-e^(-t/τ))
(4) τ=RC
The Attempt at a Solution
Ok, so I start by using (1) to find that Q=36uC, then I use (2) to find that I=.36A, but after that is where i encounter problems. I am trying to use (3) to find the charge but it's not giving me the right answer. I'm not sure how to use (4), what is that formula telling me, and am i doing everything right?
The answer should be 22uC