Approximate value of the efficiency of a threephase induction motor running at a slip s is given by

Approximate value of the efficiency of a threephase induction motor ru

1.	Approximate value of the efficiency of a threephase induction motor running at a slip s is given by
A.	<table><tr><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>1</center></td></tr><tr><td style="text-align: center;">1 + s</td></tr></table>
B.	<table><tr><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>s</center></td></tr><tr><td style="text-align: center;">1 + s</td></tr></table>
C.	<table><tr><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>1 s</center></td></tr><tr><td style="text-align: center;">1 + s</td></tr></table>
D.	<table><tr><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>s</center></td></tr><tr><td style="text-align: center;">1 s</td></tr></table>
Answer» D. <table><tr><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>s</center></td></tr><tr><td style="text-align: center;">1 s</td></tr></table>

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Approximate value of the efficiency of a threephase induction motor running at a slip s is given by

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