MEASURING OF HEAT 



133 



QUESTIONS 



1. Why do objects, which ordinarily feel cold to us, often feel 

 warm when our hands are cold? 



FIG. 100. Pipes on the 

 ceiling are provided with 

 automatic sprinklers. 



FIG. 102. The water 

 forced on the fire. 



is 



FIG. 101. The heat of 

 the fire melts the alloy. 



FIG. 103. Such devices 

 may prevent great losses. 



2. When is a pipe hot, warm, cool, and cold? 



3. Why do we blow on our soup to cool it, and on our hands to 

 warm them? 



