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1 . T h e s l i p r i n g s o f a n d i n d u c ti o n m o t or a r e m a d e o f ( a) A l u m i nu m ( b ) c a r b on ( c ) p h o s p h or b r o n z e ( d ) c o p p e r
2 . T h e r ot or w i n d i n g of a 3- p h as e wo u n d r o to r i n d u c t i o n m ot o r i s ge n e ra l l y c o n n e c t e d ( a) d e l t a ( b ) S t ar ( c ) r e ve r s e d e l t a ( d ) p a rt i a l l y s t ar p ar t i al l y d e l ta

3 . U n d e r o p e r a ti n g c on d i t i o n s t h e r o t or c i rc u i t of an i n d u c t i on m ot o r i s ( a) n o rm a l l y o p e n ( b ) o p e n e d o r c l o s e d f r e q u e ntl y ( c ) a l way s c l os e d ( d ) n o rm a l l y c l o s e d

4 . T h e p owe r f ac to r o f a s qu i r r e l c ag e l a r ge i n d u c t i on m ot o r i s ( a) L ow at h e av y l o ad s on l y ( b ) L ow at l i ght l o ad s an d h e av y l o ad ( c ) L ow at ra t e d l o ad on l y ( d ) L ow at l i ght l o ad s on l y

5 . A i r g ap fl u x d e n s i ty i s of t h e o r d e r of ( a) 0 . 35 t o 0. 6 T ( b ) 1 . 0 to 1 . 2 T ( c ) 0 . 6 to 0 . 8 T ( d ) 0 . 8 t 1. 0 T


6 . R ot o r C u l o s s = ( a) s l i p / Ro t or i n p u t p owe r ( b ) s l i p - R o to r i n p u t p owe r ( c ) R ot o r i n p u t p owe r / s l i p ( d ) s l i p x Ro t or i np u t p owe r

7 . A vo l tm e te r gi ve s 12 0 os c i l l at i o n s p e r m i nu t e w h e n c on n e c t e d t o t h e r ot o r of an I M . T h e s t a t or f r e q u e n c y i s 5 0H z . T h e s l i p o f th e m ot o r i s ( a) 2 . 5% ( b ) 5 % ( c ) 4 % ( d ) 2 %

8 . A 4 - p ol e , 5 0H z i n d u c t i on m ot o r op e r at e s at 5% s l i p T h e f r e q u e n c y o f e m f i n d u c e d i n t h e ro t or w i l l b e ( a) 2 5H z ( b ) 2 . 5H z ( c ) 1 0H z ( d ) 5 0H z

9 . I n c a s e of a 3 - p h a s e i n d u c t i on m ot o r h av i n g N s =1 50 0 r p m a n d r u n n i n g w i th s l i p = 0. 0 4 s p e e d o f th e r o to r fl u x w i t h r e s p e c t t o t he s t a to r i s r p m ( a) 1 50 0 ( b ) 6 0 ( c ) 1 44 0 ( d ) z e r o

1 0. I n a 3- p h as e i n d u c t i on m ot o r a t f u l l - l o ad ( a) t h e f re qu e n c y of s t a to r c u r r e nt i s ve r y l ow a s c om p a r e d t o t h at o f ro t or c u r re nt ( b ) t h e f re qu e n c y of r ot o r c u r r e nt i s s l i ght l y l e s s t h an t ha t o f s ta t or c u r re nt ( c ) t h e f re qu e n c y of r ot o r c u r r e nt i s ve r y l ow a s c o m p a re d t o t h at o f s ta t or c u r re nt ( d ) t h e f re qu e n c y of c u r r e nts i n s ta t or an d ro t or ar e t h e s a m e

1 1. I n a s l i p r i n g i n d u c t i on m ot i o n i f th e r ot o r r e s i s t a n c e is i n c r e a s e d th e n ( a) s t a rt i n g t o rq u e i n c r e as e b u t e ffic i e n c y d e c re as e s ( b ) s t a rt i n g t o rq u e an d e ffi c i e n c y i n c re as e ( c ) s t a rt i n g t o rq u e d e c r e a s e s b u t e ffi c i e n c y i n c r e as e s ( d ) s t a rt i n g t o rq u e an d e ffi c i e n c y d e c r e as e

1 2. P u l l o u t t or q u e o f S C I M o c c u r s a t t h at val u e o f s l i p w h e r e r o t or p owe r f ac t o r e q u al s ( a) U n i ty ( b ) 0 . 86 6 ( c ) 0 . 5 ( d ) 0 . 70 7

1 3. T h e d e e p - b a r r o to r s o r d o u b l e c a g e r o to r s a r e e m p l oye d t o ( a) r e d u c e r ot or c or e l os s . ( b ) I n c r e a s e p u l l ou t t o r qu e ( c ) I n c r e a s e s t ar t i n g t or q u e ( d ) i m p r ove e ffi c i e n c y

1 4. S ke w i n g of r ot o r s l o t s i n i n d u c ti o n m o t or i s t o ( a) i n c r e a s e th e b r e ad t h f ac to r ( b ) I n c r e a s e t h e l o ck i n g te n d e n c y o f r o to r ( c ) i n c r e a s e th e d i s t r i b u ti o n f ac t o r ( d ) R e d u c e th e m ag n e t i c hu m of m ot o r

1 5. I n i n d u c t i on mo t or s , t h e s h o r t - c i r c u i t t e s t i s t e s t ( a) b l o cke d r ot o r ( b ) n o - l o ad ( c ) o p e n - c i rc u i t ( d ) s t a to r r e s i s ta n c e


1 6. A n i n d u c ti o n m o t or e m p l oy s a s ta r ti n g d e vi c e t o r e s t r i c t a t s t ar t . ( a) l i n e c u r re nt ( b ) t or q u e ( c ) l i n e vo l t ag e ( d ) p owe r

1 7. W i t h D O L s t ar t o f an i n d u c ti o n m o t or t h e h e a ti n g d u r i n g a c c e l e r a ti o n o f i n e r ti a l o ad i s p r o p o rt i o n al to ( a) M a x i mu m t or q u e ( b ) S t or e d k in e ti c e n e r g y ( c ) e l e c tr o m a gn e t i c p owe r d e ve l op e d o n r ot o r ( d ) s l i p at m a x i mu m t or q u e

1 8. I n V /f s p e e d c ont r ol of 3 θ i n d u c t i o n m ot o r, w i t h i n c r e a s e i n f r e q u e n c y, t he m a xi mu m t o rq u e an d s l i p a t w h i ch m a xi mu m t o r qu e o c c u r s , wou l d r e s p e c t i ve l y ( a) i n c r e a s e an d i n c re as e ( b ) d e c r e a s e an d i n c r e as e ( c ) i n c r e a s e an d d e c r e as e ( d ) d e c r e a s e an d d e c r e a s e

1 9. T h e s p e e d o f a n i n d u c t i o n m ot o r d e p e n d s o n ( a) nu mb e r o f s t a t or p ol e s , s t a to r s u p p l y f re qu e n c y, i n p u t vo l ta g e t o s t a to r ( b ) i n p u t vol t a ge t o s t at o r ( c ) nu mb e r o f s t a t or p ol e s ( d ) s t a to r s u p p l y f re qu e n c y


2 0. W h i ch o f th e f o l l ow i n g i s n ot th e ad vant a ge of an i n d u c t i on ge ne ra t or ? ( a) I t i s s i m p l e an d r u gg e d i n c on s tr u c t i o n , ch e a p e r i n c os t an d n e e d s l i t tl e m ai nt e n a n c e ( b ) W h e n s h or t - c i rc u i t e d i t d e l i ve r s l i t t l e o r n o s u s ta i n e d p owe r ( c ) I t d o e s n o t hu nt o r d r o p o u t of s y n ch r on i s m ( d ) I t d e l i ve r s on l y l e ad i n g c u r r e nt

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