- Joined
- Aug 16, 2011
- Messages
- 43
- Reaction score
- 2
A discrepancy came up while I was doing a Kaplan exam that had a question about dielectrics.
Question is as follows: "
The plates of the capacitor are originally separated by
a vacuum. If a dielectric κ > 1 is introduced between
the plates of the capacitor, and the capacitor is
allowed to charge up, which of the following statements
is/are true?"
The answer was that the Charge and Capacitance of the capacitor will both increase. This makes sense if we look at the equation C=KeA/d. To explain why Q increases, Kaplan states that C=Q/V so if capacitance increases then so does Q.
But this confuses me when I read about dielectrics in TBR: "If polarilizability increases then the dielectric constant also increases", ie water K=80. But then TBR goes on to say that the stabilizability of the K medium decreases both the magnitude of charge Q on the plates and the E field.
large K as TBR states reduces Q on the plates while the equation C=KeA/d and C=Q/V tell me otherwise. What connection am I missing here?
Question is as follows: "
The plates of the capacitor are originally separated by
a vacuum. If a dielectric κ > 1 is introduced between
the plates of the capacitor, and the capacitor is
allowed to charge up, which of the following statements
is/are true?"
The answer was that the Charge and Capacitance of the capacitor will both increase. This makes sense if we look at the equation C=KeA/d. To explain why Q increases, Kaplan states that C=Q/V so if capacitance increases then so does Q.
But this confuses me when I read about dielectrics in TBR: "If polarilizability increases then the dielectric constant also increases", ie water K=80. But then TBR goes on to say that the stabilizability of the K medium decreases both the magnitude of charge Q on the plates and the E field.
large K as TBR states reduces Q on the plates while the equation C=KeA/d and C=Q/V tell me otherwise. What connection am I missing here?