This could sound ridiculous to someone with an ounce of experience, but I'm just getting started, so here we go ;) Full question is 3 parts...
First, what is the lowest amperage needed to light an LED? I think there are blue LEDs that can light up at 5 mA. 10 mA is where shocks begin to get painful.
Second, in a circuit with a battery, is there any scenario where that low voltage of a battery could deliver a painful or harmful shock if something went wrong?
Third, could you power that LED with a bare copper wire touching your skin, such as wire jewelry, or would that circuit short on your skin or provide an electric shock?
Simply, I'm trying to figure out if it's possible to wear a bare copper wire around your neck or wrist that powers an LED, or does that wire need to be insulated?
My instinct is to say no, but I'm also thinking maybe your skin would provide enough resistance to both prevent shock and force the current to continue down the wire.