how to slowly discharge a capacitor SOLVED

Is there a way that quite slowly discharge a capacitor. So i want to get a 40V capacitor, charge it the hook it to a button and short it (Not a good idea.) So as you press the button it will short the cap and the wire will heat up. This is possible with a 9V battery but a cap can hold more voltage. Basically all I need is a simple diagram that shows a good way to slowly discharge a capacitor.


by KacieA
November 13, 2016

How big is the capacitor?

November 13, 2016

330 micro farads

by KacieA
November 13, 2016

2 Answers

Answer by hevans

Hi KacieA. Welcome to the CircuitLab QA site!

The answer to this questions is almost certainly a resistor, you just have to figure out what size resistor to use. That depends on how long you want it to take to discharge the capacitor.

I set up a simple circuit here you should experiment with. Notice I have a time controlled switch, that flips at .1s. Before that your capacitor is fully charged to the 40V you stated. When the switch flips the capacitor starts discharging through the resistor.

If you check out the simulator tab, you will see I used a sweep parameter. This means that the circuit gets simulated for multiple values of R1 so you can see how much changing R affects the discharged time of the capacitor.

ACCEPTED +1 vote
by hevans
November 13, 2016


The answer is probably a resistor, but we need to know how big your capacitor (how many farads) is before we can help answer this question.

+1 vote
November 13, 2016

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