410 GENERAL SCIENCE 



A Battery. A battery is a number of cells united in series or 

 parallel. Sometimes a single cell is called a battery. This, of 

 course, is an incorrect use of the word. 



QUESTIONS 



1. Why is the voltage marked on the lights in your home? 



2. What would be the effect of placing a lamp marked 110 volts 

 on a current which had a pressure of 220 volts? 



3. Why are flatirons, vacuum cleaners, etc., marked with both 

 amperes and volts? 



4. What causes the telegraph instrument to tick when one 

 presses the key? 



5. Why are " dry cells " called dry cells? 



6. Why are lights in a home wired in parallels? 



7. What would be the effect if the lights were wired in series and 

 one light went out? 



