A capacitor consists of two metal plates separated by an insulator, as shown in the figure below.
The potential difference between the plates is 
. The variation with of the magnitude of the charge 
on one plate is shown in the graph below.
Explain why the capacitor stores energy but not charge.
Use the graph above to determine the capacitance of the capacitor.
Three capacitors X, Y and Z, each of capacitance 
, are connected as shown in the figure below.
Initially, the capacitors are uncharged. A potential difference of 
is applied between points A and B. Determine the magnitude of the charge on one plate of capacitor X.
.
.
