Why Is Charge Measured in Nanofarads Instead of Coulombs?

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Charge is measured in coulombs, not nanofarads, as the formula Q = CV indicates, where Q is charge, C is capacitance in farads, and V is voltage in volts. The confusion arose from a misinterpretation of the units in the lab calculations. The correct calculation shows that 4.7 nanofarads multiplied by 30 volts results in 141 nanocoulombs, not nanofarads. This highlights the importance of understanding unit conversions in physics. Clarifying these units ensures accurate measurements and calculations in experiments involving capacitors.
AngelofMusic
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Hello,

We haven't covered capacitance in class yet, but our lab involves the use of capacitors, so I thought I'd throw out a general question.

We were asked to use the MOS FET Electrometer to measure charge, and we were given the formula:

Q = CV

Where C is the capacitance, and V is the potential difference. C is measured in Farads and V in volts.

I'm just confused because in the sample calculations provided by the lab handout, we had:

Qinit = CV = 4.7x10^-9 [F] X 30 [V] = 141 [nF]

How come the unit for charge ended up being in nanofarads, and not in coulombs or nanocoulombs or anything like that?

Any clarifications would be appreciated!
 
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That has to be a typo.

1 Farad is defined as 1 Coul./Volt

You have 4.7 nF x 30 V = 141 nC
 
Okay, that makes a lot more sense.

Thanks!
 
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