What is the charged stored by a 15 nF capacitor, if it is connected to a 4.5 V battery

Question

A. 0.3 nC

B. 3.33 nC

C. 6.75 nC

D. 67.5 nC

Answer 1

Capacitance is charge divided by voltage, C = Q / V.

Expressing the capacitance in Farads, you get 15 x 10^-9. Putting this in the equation, and solving for Q, Q = CV = 15 x 10^-9 F x 4.5 V = 6.75 x 10^-8 Coulombs which is 67.5 nC.