Electric Generator||Domestic Electric Circuits

What is the main difference in the wiring of an electric bulb and a socket for using an electric iron in a domestic electric circuit ? What is the reason for this difference ?

The electricity meter in the domestic electric circuit measures electrical energy consumption in kilowatt. Hours.

The electricity meter in the domestic electric circuit measures electrical energy consumption in kilowatt hours. Is it true? Also express 1 kilowatt hour in joules.

Electric Current||Electric Circuit

Electric Bulb|Electric Circuit|OMR

Is the electric potential difference across each appliance (in a domestic electric circuit) the same?

What is the colour of neutral wire in a domestic electric circuit?