mobile chargers etc

[sweetandsour]

We are told to switch off chargers when they are not in use as they waste electricity. Question Where does it go?

[ACtheTROLL]

it drips out of the plug and ruins the carpet

Nothing is perfect - and the mismatch causes current to flow.
(if you put your ear to a transformer - you hear a buzz - feel it - and it will be warm (or hot))

and generating noise and heat is wasteful - for something that's supposed to be filling up a battery .... or whatever

[compostheap]

Electricity runs from live to nuetral. Your phone charger is a transformer converting 240volts AC to a low DC voltage . Although the phone is not connected, the transformer is still "using" a small amount of current , it,s a bit like boiling your kettle and not using the hot water, after a few minutes it will need to be re-boiled !