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प्रश्न
Answer the following question.
Give any four applications of thermal conductivity in everyday life.
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उत्तर
- a. Thick walls are used in the construction of cold storage rooms.
b. Brick being a bad conductor of heat is used to reduce the flow of heat from the surroundings to the rooms.
c. Better heat insulation is obtained by using hollow bricks.
d. Air being a poorer conductor than a brick, it further avoids the conduction of heat from outside. - Street vendors keep ice blocks packed in saw dust to prevent them from melting rapidly.
- The handle of a cooking utensil is made of a bad conductor of heat, such as ebonite, to protect our hand from the hot utensil.
- Two bedsheets used together to cover the body help retain body heat better than a single bedsheet of double the thickness. Trapped air being a bad conductor of heat, the layer of air between the two sheets reduces thermal conduction better than a sheet of double the thickness. Similarly, a blanket coupled with a bedsheet is a cheaper alternative to using two blankets.
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