Circuits and Resistors question

[ihatebluescrubs]

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Is there any difference between a circuit where we have a battery and just a Capacitor vs the same circuit but with a added resistor? Will the addition of the resistor change the capacitance or anything else (current?)

Thanks,

 

[sazerac]

Is there any difference between a circuit where we have a battery and just a Capacitor vs the same circuit but with a added resistor? Will the addition of the resistor change the capacitance or anything else (current?)

Thanks,

Fundamentally, no. It's just a little weird to ask a question like "what is the current trend in the wire on the left" versus "what is the current trend through the resistor labeled A".

Also, if you get asked about how long it takes to charge or half-charge a capacitor or get asked what is the time constant of the system, there is that equation that involves e^(t/RC) so it's nice to have an explicit resistor to plug into that equation versus trying to estimate the internal minuscule resistances of the wires and the battery itself.


Interesting trivia: like any number, the number "e" can only be raised to a unitless number. Therefore (t/RC) is unitless. Therefore the unit of RC is the same as t. Therefore "one ohm-farad" is the same thing as "one second". There are 60 ohm-farads in a minute, etc.