Advertisements
Advertisements
Question
How does a fever get lowered by putting a cold compress on the forehead of a patient?
Advertisements
Solution
A cold compress is made up of material that absorbs heat. Thus, by putting it on the forehead of a patient suffering from high fever, the heat flow takes place from the head of the patient to the cold compress. Therefore, the cold compress absorbs heat from the patient's body and lowers the body temperature.
RELATED QUESTIONS
Give two examples each of conductors and insulators of heat.
No medium is required for transfer of heat by the process of ______.
Look at Figure. Mark where the heat is being transferred by conduction, by convection and by radiation.

Write true or false for a given statement.
Medium is necessary for the transfer of heat by radiation.
Write true or false for a given statement.
Liquids are heated by conduction and radiation.
Fill in the blank
Heat transfer in solids is by ______
Select the correct alternative
The vacuum kept in between the walls of a thermos flask reduces the heat transfer by
Maximum heat is absorbed by a ______ coloured object.
When a liquid boils, energy is absorbed.
Take two similar transparent glass bottles having wide mouths. Put a few crystals of potassium permanganate or pour a few drops of ink in one bottle. Fill this bottle with hot water. Fill the other bottle with cold water. Cover the cold water bottle with a thick piece of paper such as a postcard. Press the postcard firmly with one hand and hold the bottle with the other hand. Invert the bottle and place it on top of the hot water bottle. Hold both the bottles firmly. Ask some other person to pull the postcard. Observe what happens. Explain.
