ril in Kgi \ ii"N . ii'K IT 



When tin- rate of working i* given in horse-power 

 the equation for tin- induction factor may be written 



) ......... (; 



H - //' i- the boree-power on the motor shaft, and /< 

 the revolutions per second. 



Example 14. A motor lias to do work at the rate 



kilowatt*. the tension of the line is \'2-> volt*, the 



resistance of the motor is 0-OG ohm, the speed has to be 



1 It'"- 

 lution.s |MT minsto. The expression 



to be 0-1U7, and the term un.i- i the root is 

 0*893. Hence the value of the induction factor is 

 If a motor with this induction factor and 

 the given resistance be connected to a line having a 

 tension of 1 .' it will run at 1,JUO revolution* 



per minute when working at the rate of 7 kilowatts. 

 By taking the negative oigu insidi* the bracket. \\. 

 see that a motor with an indurtii*n factor of "172 would 

 also fulfil these condition*. *.. thai we need some further 

 nation to guide os as to which value of M t 

 dopi. 



\\ know that the current is given by trmcltn ; from 



we find that with an induction factor of 



rhr current would be 68 amperes, while with an 



indii. -ti..n factor of 01 7J it w.-.iid I amperes. 



The I ;y ini|Mh.-ible. though we must not 



forget that even when carrying tlii. nrn-nt the 



runniu- at the -iven Speetl nrautaiin* 



remained unaltered. 



