ELECTROMOTIVE FORCE 5 



used up in resistance, and how many ohms will be needed? (3 

 ram.) 



13. The shunt-field resistance of a 10-kw., 120- volt generator 

 is to be measured. A rheostat is in series with it on the 120-volt 

 circuit. The current is 2 amperes and the drop around the field 

 is 106 volts. What is the resistance of the field, of the rheostat 

 and of the combination? (2 ram.) 



14. In measuring a certain railway current a "shunt" having 

 a resistance of 0.00025 ohms is connected in the circuit, and a 

 millivoltmeter attached to its terminals reads 0.05 volts. What 

 is the value of the current? Why should the resistance in this 

 shunt be so low? (2 ram.) 



