ELECTRIC CELLS 



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4 Posts 



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tricity would flow for just an instant from one body to the 

 other. Electricity in motion as this is, is called current 

 electricity. This is the kind of electricity which we use 

 in ringing our doorbells, in running our motors, and in 

 lighting our homes. We have all seen what electricity 

 will do, and now we will try to understaad how to produce 

 it, and some other things which we can do with it. 



Electric cells. You may have heard the terms, dry cell 

 and wet cell, and doubtless some of you have seen them in 

 your homes, as these two 

 kinds of cells are used 

 to ring electric doorbells. 

 The wet cell is made by 

 nearly filling a jar with 

 a saturated solution of 

 sal ammoniac. In this 

 are suspended side by 

 side, but not touching 

 each other, a large car- 

 bon plate and a zinc rod. 

 Electricity is formed at 

 the expense of chemical 

 energy, and the zinc rod 

 which is destroyed must 

 be replaced from time 

 to time. 



In the dry cell, the 

 zinc used is placed on 

 the outside of the cell while the carbon is a large rod in 

 the center. Between these are the chemicals, a paste of 

 sal ammoniac being placed next the zinc, and a layer of 

 manganese dioxide around the carbon. Dry cells, because 



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Sakxmmoniac 

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Heavy Tar Paper 



Section of a dry cell. 



