Switch S shown in the figure below has been closed for a long time, and the electric circuit carries a constant current. Take
C1 = 3.00 μF
C2 = 6.00 μF,
R1 = 4.00 kΩ,
R2 = 7.00 kΩ.
The power delivered to R2 is 2.30 W.
(a) Find the charge on C1.
(b) Now the switch is opened. After many milliseconds, by how much has the charge on C2 changed?
The Attempt at a Solution
To find the charge on C1 I would use Q=CV, but first I would need to find the voltage or substitute one of the other equations.
I looked at the solution, and it gives me this image (different values):
I have no idea why it can be rearranged like this, since even the capacitors/resistors change places.
My first plan was using the fact that R2 is given power of 2.30W, so then I would use P=IV and V=IR to get P=I2R. Solve for I and I get the current there. However, according to the solution it determines the current of the whole thing. I don't see how that's possible from either arrangement.