GENERATION OF K.M.F.

II

Such a machine is called a "unipolar," or more properly it
"non-polar" or an "Acyclic," generator.

14. (2) The field spools of the 20-polo alternator in Sort ion
1, Example 4, are wound each with 016 turrw of wirn No. 7
(B. & S.), 0.106 sq. em. in croBB noction ami 100 «m. mean length
of turn. The 20 spools are connected in fwrien. How ninny
amperes and how many volts are required for the excitation «f
this alternator field, if the resistivity of copper in 1.8 X JO'*
ohms per em.31

FIG. 4.-—Unipolar gimorator. *

Since 016 turns on each field npool are UHCK!, ami 4'28() itrtip«,*rt*«
turns required, the current ii fi-fl » 6.95 «,mp.

The resistance of 20 spools of (111} tttriw of Hill urn.
0.106 sq. cm. section, and 1.8 X 10 lf rcwKtivity in,

20X616X 160 X 1.8X 10 «

#/ **#!»*

and the e.m.f. required, 0,95 X 83.2 « 230 voltn.

3. GENERATIOK* Of

16. A closed conductor; convolution or turn. In n

magnetic field, during each involution two

positions of maximum inelomirn of linw of tnitgtii*tift ftirni
A in Fig. 5, and two positions of &ero of of

netic force B ia Fig. 5.

^ cm.» refers to a cube whoise »4e ii i GU,, sad iti4 tm

with eu, cm,