EXERCISE 58 



IS THERE A DIFFERENCE IN THE RATES AT WHICH SOIL AND WATER 



CHANGE IN TEMPERATURE? 



Materials. Bunsen burners or alcohol lamps ; metal cups or pans (not soldered) ; soil ; water ; 

 thermometers. 



Directions. Arrange two Bunsen flames, or alcohol-lamp flames, to burn as nearly alike as pos- 

 sible. Place about 100-200 grams of dry soil in a cup and an equal weight of water in a second 

 cup. Take the temperatures of both and leave a thermometer in each; then place them over the 

 burners at the same time. When one reaches about 100 C. or 21 2 F., note the temperature of 

 the other and record both. Which heats more rapidly? 



Additional problems. If a 5-pound piece of iron at 100 C. be dropped into a vessel containing 5 pounds 

 of water at C., the water will be warmed and the iron cooled. What is the temperature at which the 

 water is no longer heated by the iron ? 



On the beach at noon of a bright summer day, is the sand of the beach or the water warmer ? Do 

 the same temperature relations exist at midnight? In the beginning of winter weather does the sand 

 along the shore or the water freeze first ? 



Which heats more rapidly upon a stove, a kettle of water or an iron of equal weight ? 



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