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I'm sorry if this has been asked, as it's a simple question, but I haven't found it.
Is there any reason why capacitors are built in so fixed values? For any other components the manufactured value are round numbers, for example resistors
100 Ohm - 1 kOhm - 10 kOhm - ... but capacitors come in weirder numbers, specifically, why can you find multiples of 4.7? is there anything special about that number? is there any normal circuit that goes on everything that needs a capacitance like that?