How are electrical appliances connected to the main line in our homes?

Mention the voltage and frequency of the electric current that we receive in our houses.

$(a)$ What is the function of an earth wire in electrical instruments? Why is it necessary to earth the metallic electric appliances?
$(b)$ Explain what is short-circuiting and overloading in an electric supply.
$(c)$ What is the usual capacity of the fuse wire in the line to feed:
$(i)$ lights and fans?
$(ii)$ appliances of $2 \,kW$ or more power?

$(a)$ Electric fuse is an important component of all domestic circuits. Why?
$(b)$ An electric oven of rating $2 \, kW, 220 \, V$ is operated in a domestic circuit with a current rating of $5 \, A$. What result would you expect? Explain.

In an electric circuit,a fuse is used because $......$

$(a)$ Mention the colour code used for live,neutral,and earth wire.
$(b)$ You want to connect a $2 \ kW$ electric oven in the electric circuit. In which power line would you connect it and why? What may happen if you connect it wrongly in the other power line?