72 ELECTRICAL ENGINEERING PROBLEMS 



15. A wattmeter is to measure power in a .circuit having a 

 maximum angle of lag of 36 degrees; the periodicity is 60, and the 

 resistance of the wattmeter shunt is 1000 ohms. How small must 

 the value of L be in the wattmeter in order to get the results 

 correct to within i of 1%? The same problem, but with an angle 

 of lag of 60 degrees. (6 min.) 



