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Common Science 



FIG. 170. The air openings in the front of a gas stove. 



kind of radiant heat? Of course the yellow flame is the 

 hottest. Leave the stove alone." 

 Who was right? 



Inference Exercise 

 Explain the following : 



441. Iron tracks are welded together with an electric arc. 



442. The cool mirror in a bathroom becomes covered with mois- 



ture when you take a hot bath. 



443. This prevents you from seeing yourself in the mirror. 



444. Carbon dioxid has oxygen in it, yet a burning match dropped 



into a bottle of it will go out. 



445. A ship that sinks to the bottom of the ocean does not decay. 



446. When women put their hair in curlers, they usually moisten 



the hair slightly. 



447. To dry a pan after washing it, a person often sets it on the 



hot stove for a few minutes. 



448. When you put a kettle of cold water over a gas flame, drops of 



water appear on the lower part of the sides of the kettle. 



449. Electric power plants are often situated where running water 



will turn the dynamo. Explain the necessity of turning 

 the dynamo. 



450. We make carbon dioxid by burning carbon, but you cannot 



put different things together to make carbon. 



