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Role of resistance? Answered

What if we charge a capacitor without resistance. What will happen? My teacher taught me that without the presence of external resistance capactors charge and discharge instantly.

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randofoBest Answer (author)2017-04-30

Not quite instantly, but yes. That is more or less accurate.

A resistor serves to slow down the charge rate of the capacitor.

What you are talking about is an RC timing circuit. Here is a description, which is a bit confusing about how they work:


If you understand microcontrollers, you can take a look at the "RCtime" example. In this circuit the Arduino counts the amount of time it takes a capacitor to charge through a resistor. So, if you increase resistance, the amount of time increases (and a decrease would decrease the time). This is a little easier to wrap ones head around (assuming you understand Arduino at all).


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