15. Long answer questions II

  

The ring in the spade's iron blade is heated first. The blade contractsexpands as it heats up, decreasingincreasing the size of the ring. This occurs because metals expand when heatedmetals contract when heated. The metal blade is then inserted into the wooden handle easily. After that, cold water is usually put on the iron blade, causing the expanded iron blade to contractcontracted iron blade to expand. The spade can also be let to cool down undisturbed to fix it firmly. (vu) In this technique, the blade is firmly attached to the wooden handle of a spade.