# A question involvingn safe working voltage and capacitors?

1. Oct 19, 2011

### jackcie

1. Problem Statement
Some capacitors are marked 48uF, safe working voltage 25V.
Show how a number of these capacitors may be connected to provide a capacitor of capacitance:
a) 48uF, safe wroking voltage 50V
b) 72uF, safe working voltage 25V

2. Relevant Equations
obviously C total in parallel = c1 + C2... and 1 / C total in series = 1/ C1 + 1 / C2

3. Attempt at the Solution
for part a) i thought you could have two of the capacitors in parallel, followed in series by another two capacitors in parallel for b) i didnt really have a clue, but perhaps two in series? (im probably wrong!)

the answers state that for part a) "two capacitors in series", such that V < 25V across each capacitor.
for part b)"two capacitors in parallel with a single capacitor"

what is the safe working voltage??

Last edited by a moderator: Oct 19, 2011
2. Oct 19, 2011

### Mindscrape

Hint: what is the safe energy in the original capacitor set up?