Question

A sphere has a potential difference between it and the earth of 5 V when charged with 14 nanocoulomb. What is the capacitance?

Answer 1

The capacitance is given as follows (see https://physics.nfshost.com/textbook/09-Capacitance/01-Definition.php):

$$C = \dfrac{Q}{\Delta V}$$

where $Q = 14\times 10^{-9}C, \Delta V = 5V$. Thus, obtain:

$$C = \dfrac{14\times 10^{-9}C}{5V} = 2.8\times 10^{-9}F$$

Answer. $2.8\times 10^{-9}F$.