The plates of a parallel-plate capacitor have constant charges of + Q and Q . Do
ID: 1427188 • Letter: T
Question
The plates of a parallel-plate capacitor have constant charges of +Q and Q. Do the following quantities increase, decrease, or remain the same as the separation of the plates is increased?
I have the correct answers which are:
The electric field between the plates stay the same
The potential difference between the plates increases
The capacitance decreases
The energy stored in the capacitor increases
I'm just having trouble explaining why it is those answers. Can someone help explain them for me?
Explanation / Answer
A) E decreases – E-field in the dielectric opposes the field between the plates
B) V decreases because C increases.
C) C increases by factor , the dielectric constant.
D) U decreases – the formula is U= 1/2 CV^2
. C goes up, but V goes down.