What is the process of depositing a layer of gold on silver called?

The resistance of a piece of rubber is higher than that of a piece of copper of the same dimensions.

$A$ house is fitted with $5$ tubes each of $40 \, W$. If all the tubes are lighted for $20$ hours and if the cost of electrical unit is ₹ $0.50$,the total cost of electricity consumed is (in ₹)

When an electric iron is connected to a $220\;V$ line and a current of $5\;A$ flows through it,what is the power of the iron?

Electrical resistivity of a given metallic wire depends upon

How can we maintain a potential difference across a conductor?