How can I show that the RC circuit has dimensions of time? 1 second = 1ohm x 1farad?
Expand out Ohm and Farad in terms of base units and simplify.
time constant = R x C
Ohm's Law and the well-known relation between Q,C & V will help with that.
Or use technician's suggestion, but somehow that feels like a cheat to me.
I agree! The time constant confirms that RC must be seconds but you do need to determine the dimensions of R and C.
You have a similar post regarding volts, webers and seconds. Faradays law gets you started but here also the quantities webers, volts etc need to be expressed as dimensions
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