Answer
(a) $C_{eq} = N\times C$
(b) $C_{eq} = \frac{C}{N}$
Work Step by Step
(a) We can find the equivalent capacitance $C_{eq}$:
$C_{eq} = C + C +...+ C~~~$ (Note that $C$ is added $N$ times)
$C_{eq} = N\times C$
(b) We can find the equivalent capacitance $C_{eq}$:
$\frac{1}{C_{eq}} = \frac{1}{C} + \frac{1}{C} +...+ \frac{1}{C}~~~$ (Note that $ \frac{1}{C}$ is added $N$ times)
$\frac{1}{C_{eq}} = \frac{N}{C}$
$C_{eq} = \frac{C}{N}$
