EMWT ONLINE 5

1 . Fo r n o r m al i n c i d e n c e of th e wave on p e r f e c t c on d u c t o r
( a) S u r f a c e c u r r e nt e x i s t ( b ) Fr e e ch ar g e e xi s ts o n t h e s u rf ac e ( c ) C o n d u c t i on c u r re nt e xi s t ( d ) S u r f a c e c u r r e nt d o e s n t e xi s t

2 . I n th e c a s e of p e r p e n d i c u l a r p o l ar i z a t i on
( a) T h e H i s p e r p e n d i c u l a r t o t h e p l a n e o f i n c i d e n c e an d p ar a l le l t o t h e r e fl e c ti n g s u r f a c e
( b ) T h e E i s p a ra l l e l t o t h e p l an e of i n c i d e n c e an d p e r p e n d i c ul a r t o t h e r e fl e c ti n g s u rf ac e
( c ) T h e H i s Par a l l e l t o t h e p l a n e of i n c i d e n c e an d p e r p e n d i c u l a r t o t h e r e fl e c ti n g s ur f a c e
( d ) T h e E i s p e r p e n d i c u l ar t o t h e p l a n e of i n c i d e n c e an d p ar a l l e l t o t h e r e fl e c ti n g s u rf ac e

3 . T h e c r i ti c al an g l e i s g i ve n by
( a) Tan Θ = S q r t ( ∈ 2 / ∈ 1 ) ( b ) Tan Θ = S q r t ( ∈ 1 / ∈ 2 ) ( c ) S i n Θ = S q r t ( ∈ 1 / ∈ 2 ) ( d ) S i n Θ = S q r t ( ∈ 2 / ∈ 1 )

4 . T h e p o i nt i n g ve c t or gi ve s
( a) T h e d i r e c t i on of E fi e l d ( b ) T h e d i r e c t i on of wave p r o p ag at i o n ( c ) T h e d i r e c t i on of H fi e l d ( d ) T h e d i r e c t i on of b o th E a n d H fi e l d s

5 . I f r e fl e c t i o n c o e ffi c i e nt = - 1 / 2 t h e n t h e s w r i s
( a) O n e ( b ) Z e ro ( c ) 3 ( d ) 1 /3

6 . Fo r a z p r op a ga t i n g e m wave , i f p ro p a ga ti o n c on s t a nt i s r e a l t h e n (
a) N o wave m ot i on ( b ) T h e wave t r ave l s i n z d i re c ti o n ( c ) Wave t r ave l s w it h an e x p on e nt i a l d e c r e a s e i n a m p l i tu d e ( d ) Wave t r ave l s w it h n o ch an g e i n am p l i t u d e

7 . O th e r n am e of T E wave i s
( a) U n i f o r m p l a ne wave ( b ) H wave ( c ) E wave ( d ) E & H wave

8 . I f op e r at i n g f r e q u e n c y i s g re at e r t h a n t h e c u to ff wave l e n gt h , th e n
( a) α = β ( b ) α = Z e ro ( c ) α = i n fi n i ty ( d ) α = 1 / β

9 . A m o d e w h i ch d o e s n ot p ro p a ga te i s
( a) E van e s c e nt m o d e ( b ) D om i n a nt m o d e ( c ) P r i n c i p a l wave ( d ) T E m o d e

1 0. W h e n a wave i s tr ave l i n g i n Z d i re c ti o n , t h e n i t s i mp e d an c e i s gi ve n by ( a) - E y / H x ( b ) E y / H x ( c ) E x / H y ( d ) - E x / H y

1 1. A two c o n d u c t or t r a n s m i s s i o n l i n e s u p p o rt s
( a) T E M m o d e wave ( b ) T M m o d e wave on l y ( c ) T E m o d e wave on l y ( d ) B o t h T E a n d T M m o d e wave s

1 2. T h e u n i t f o r at t e nu a ti o n c o n s t a nt i s
( a) d B / m ( b ) Vo l t /m ( c ) A m p . / m ( d ) R ad i a n / m

1 3. A l o s s y tr a n s m i s s i o n l i n e
( a) N o n D i s p e r s i ve ( b ) I t mu s t b e a d i s to r ti o n l e s s l i n e
( c ) H ave i n fi n i te l os s ( d ) D i s p e r s i ve



1 4. I f L T a n d C T a re t h e to t al i n d u c t an c e a n d to t al c a p ac i t a n c e of t h e l i ne i n c l u d i n g th e l o ad i n g c o i l s , t h e n i t s c u t o ff f r e q u e n c y i s g i ve n by
( a) 1 / ( π . s q r t (L T C T ) ) ( b ) π / s q r t (L T C T ) ( c ) π . s q r t (L T C T ) ( d ) 1 / ( 2 π . s q r t (L T C T ) )

1 5. A l ow l o s s t ra n s m i s s i on l i n e o p e r at i n g a t 10 0 M H z h a s L = 0. 2 5 m i c r o h e n r y/ m , C = 1 00 p F / m . T h e n t h e p h as e c o n s t ant i s
( a) 1 / π ( b ) 2 π ( c ) π ( d ) 3 π


1 6. I n p u t i m p e d an c e o f a s h o r t c i r c u i t e d t r a n s m i s s i o n l i n e b e c o m e s
( a) P u r e re s i s t i ve ( b ) c o m p l e x q u ant i ty ( c ) Z e ro ( d ) P u r e re ac t i ve

1 7. A s h or t c i r c u i t e d λ / 4 l i n e c a n b e u s e d as
( a) A c ap a c i t or ( b ) A n i n d u c to r ( c ) A n i n s u l at o r ( d ) A c on d u c t o r

1 8. O n a t ra n s m i s s i on l i n e V m a x a n d V m i n a re s e p a r at e d by th e d i s t a n c e o f ( a) λ / 8 ( b ) λ / 2 ( c ) λ / 4 ( d ) λ


1 9. T h e s t u b l e n g t h t o b e ad j u s t e d
( a) To n e u t ra l i z e th e s u s c e p t an c e of t h e l o a d ( b ) To i n c r e as e t h e s u s c e p t a n c e o f th e l oa d ( c ) To d e c r e as e t h e s u s c e p t a n c e of t h e l o ad ( d ) N o t t o ch an g e t h e s u s c e p t a n c e of t he l o ad

2 0. T wo ve r y l o n g l o s s l e s s c ab l e s of ch a r ac te ri s ti c i mp e d an c e s o f 36 oh m s an d 1 00 oh m s r e s p e c t i ve l y a r e t o b e j oi n e d f o r r e fl e c t i o n l e s s t r an s m i s s i on . T h e Z 0 o f a m a tch i n g t r a n s f o rm e r i s
( a) 3 6 oh m s ( b ) 1 /3 6 oh m s ( c ) 6 0 oh m s ( d ) 1 00 o h m s

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