Example (cont.)
As we can see from the previous example, a Farad is a huge capacitance!
If we have a DV = 20 volts, then to calculate the charge, Q, we can use: C = Q/V to get:
Q = C*V = 11 x 10-12 F * 20 volts =
2.2 x 10-10 Coul = 0.22 nCoul = 220 pCoul.
Note that we often drop the D in front of the V since we often are concerned by the change in voltage rather than the absolute value of the voltage - just as we do when we talk about height!