Advertisements
Advertisements
प्रश्न
Write true or false for a given statement.
On touching a lump of ice, we feel cold because some heat passes from our body to the ice.
पर्याय
True
False
उत्तर
True.
APPEARS IN
संबंधित प्रश्न
A wooden spoon is dipped in a cup of ice cream. Its other end ______.
Write true or false for a given statement.
Black surfaces are the poor absorbers of heat radiations.
Explain briefly the process of heat transfer by radiation.
Maximum heat is absorbed by a ______ coloured object.
______ of heat does not require a medium.
Why are heaters fitted near the floor and air conditioners near the ceiling of a room?
When ice changes into a liquid, it absorbs energy.
Wrap a thin paper strip tightly around an iron rod. Try to burn the paper with candle while rotating the iron rod continuously. Does it burn? Explain your observation.
Take a sheet of paper. Draw a spiral on it as shown in Figure. Cut out the paper along the line. Suspend the paper as shown in Figure above a lighted candle. Observe what happens. Think of an explanation.
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.