If I were to take a standard AC to DC converter, say a laptop charger, and hook up the input side (which expects 120VAC at 60Hz) to a DC power supply of some sorts, will the electricity still be “converted,” or will it just not work at all? I am clearly very uneducated when it comes to electronics (albeit working on it) so I would very much an ELI5 answer Thanks!
Depends on how it works. I would expect that some would work but soon fail due to some components being overstressed, and others not to work at all.
I’m not an expert but as it is commonly explained, the first component of many (all?) switched mode power supplies (almost all laptop power bricks are SMPS) is a rectifier. If you feed a full bridge rectifier with DC, half of it will be unused while the other will carry all the current. The rest of the power supply after that should not care.
So in theory it should work, at least up to roughly half the rated load. But there may be other components like power factor correction circuits, safeties, or some details that those descriptions glossed over that make it not work.
Counterintuitively, if the device supports a wide voltage range (as many do) higher voltages may be better (as in less likely to fry it) as they require less current.