Fig. 1 and 2 show a dielectric slab being inserted between the plates of one of two identical capacitors, capacitor 2. Select the correct answer to each of the statements below (enter I for `increases', D for `decreases', or S for `stays the same').
In Fig. 2, the potential difference between the plates of capacitor 2 _______ when the dielectric is inserted.
In Fig. 2, the charge on capacitor 1 _______ when the dielectric is inserted.
In Fig. 1, the capacitance of capacitor 2 _______ when the dielectric is inserted.
In Fig. 1, the potential energy stored in capacitor 1 _______ when the dielectric is inserted.
ΔV = Q1/C1 = Q2/C2 ( parallel )
Ceq = C1 + C2 ( parallel )
C = Cok
Q is distributed evenly over two capacitors in series.
The Attempt at a Solution
A. Stays the same. ΔV over a capacitance in parallel always remains the same.
B. ΔV = Q1/C1 = Q2/C2, when C2 increases (C = Cok), Q2 will increase as well to compensate. Qnet = Q1 + Q2, this means Q1 must decrease.
C. C = Cok, therefore C increases.
D. 1/Ceq = 1/C1 + 1/C2. when C2 grows larger, 1/C2 grows smaller resulting in a smaller C1. V1 = Q2/(2*C).
I've revised this many times and I still can't see what I'm doing wrong. Any help muchly appreciated, thanks!
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