226. The characteristic impedance of a coaxial cable depends on:
     1. Ratio of outer and inner diameter
     2. Length of the cable
     3. Logarithmic ratio of outer and inner diameter
     4. Logarithmic ratio of outer and inner diameter and inversely as the square root of dielectric constant.
     The correct statement is/are—

1. 1. 3 and 4

   
   
   

   2. 2 and 3

   
   
   

   3. 1, 3, 4

   
   
   

   4. 4 only

   
   
   

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1. View Hint View Answer Discuss in Forum

   The characteristic impedance of a coaxial cable depends on logarithmic ratio of outer and inner diameter and inversely as the square root of dielectric constant.
   

   Correct Option: D

   The characteristic impedance of a coaxial cable depends on logarithmic ratio of outer and inner diameter and inversely as the square root of dielectric constant.
   

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227. Match List-I with List-II and select the correct answer using the codes given below the lists:
     

     List-I	List-II
     (a) Electric field E	1. amp/metre2
     (b) Magnetic flux density B	2. coulomb/metre3
     (c) Current density J	3. amp/metre
     (d) Magnetic field strength H	4. volts/metre
     	5. tesla

1. 1. (a) (b) (c) (d)
      5   4   1   2

   
   
   

   2. (a) (b) (c) (d)
      4   3   2   1

   
   
   

   3. (a) (b) (c) (d)
      1   4   2   5

   
   
   

   4. (a) (b) (c) (d)
      4   5   1   3

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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228. The inconsistency of continuity equation for time varying fields was corrected by Maxwell and the correction applied was—

1. 1. Ampere's law, δD/ δt

   
   
   

   2. Gauss's law, J

   
   
   

   3. Faraday's law, δB/ tδ

   
   
   

   4. Ampere's law, δP/ δ t

   
   
   

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1. View Hint View Answer Discuss in Forum

   Ampere's law.

   Correct Option: A

   Ampere's law.

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229. Match List-I with List-II and select the correct answer using the codes given below the lists:
     

     List-I	List-II
     (a) ∇ × E = 0	1. ∮ H⋅ dl = ∫ J⋅dA
     (b) ∇ ⋅D = ρ	2. ∮ E⋅ dl = 0
     (c) ∇ × B = μ0J	3.∮ B⋅ dA = 0
     (d) ∇ ⋅ B = 0	4. ∮ E⋅ dA = ∫ ρdV

1. 1. (a) (b) (c) (d)
      1  2  3  4

   
   
   

   2. (a) (b) (c) (d)
      2  3  1  4

   
   
   

   3. (a) (b) (c) (d)
      3  4  1  2

   
   
   

   4. (a) (b) (c) (d)
      2  4  1  3

   
   
   

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1. View Hint View Answer Discuss in Forum

   A – 2, B – 4, C – 1, D – 3

   Correct Option: D

   A – 2, B – 4, C – 1, D – 3

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230. An air filled rectangular waveguide has dimensions 6 cm, 4 cm. The cut-off frequency for TE₁₀ is—

1. 1. 2.5 GHz

   
   
   

   2. 25 gHz

   
   
   

   3. 25 MHz

   
   
   

   4. 5 GHz

   
   
   

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1. View Hint View Answer Discuss in Forum

   The relation is f_c = c/2a

   Correct Option: A

   The relation is f_c = c/2a

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