How can iron be protected from rusting by sacrificial protection ?

Explanation

Sacrificial protection of Iron : This method involves the covering of iron surface with a layer of more active metal than iron. The active metal (say Zn) loses electrons in preference to iron and goes into solution. Therefore, the covering metal is used up with time but as long as it is present, iron is not rusted. this type of protection is called sacrifical protection. metal like zinc aluminium, magnesium are used in sacrificial protection as the oxidation potential of these metals are higher than oxidation potential of iron.