Question

Give reason: To open a tightly fitted metal cap it is heated carefully.

Answer 1

We know that on heating, the expansion of metal will occur. With an increase in temperature, the dimension of the cap, such as length, volume, and surface area will increase. This expansion changes from metal to metal since the degree of thermal expansion is different for different metals. We will use this property of a metal to conclude our answer.

Complete step by step answer:
We know that by increasing the temperature, the dimensions of the metal will change. The change includes the increase in length, its surface area, and its volume. This change can be termed as thermal expansion. The extent to which this thermal expansion will occur varies from metal to metal. On increasing the temperature, the vibration of the atoms will occur in the metal, and as a result of that, the thermal expansion will occur. Therefore, when we heat the fitted metal cap up to a certain limit, its expansion will occur, but there is a limit of temperature up to which we can heat the cap as if the bottle is made of glass then on heating it on higher temperature may lead to its breakage. Hence, we can say that heating the metal cap will make it easy for us to remove it from the bottle.

Note: There are certain effects of heat on the metal, which can be categorized as the change in electrical resistance, thermal expansion of the metal, changes in its structure, and change in its magnetic properties. In this question, we are considering the thermal expansion of the metal on heating.