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PREVIOUS YEAR (2020) COMMON P.G ENTRANCE PHYSICS QUESTION SOLUTION -2

   *FOR QUESTION 1-35 ; CLICK THE LINK  https://biswatutorialphysics.blogspot.com/2021/08/previous-year-2020-common-pg-entrance.html Q/36.   The Poynting vector S of an electromagnetic wave is ?   (A) 𝑆 = 𝐸⃗ × 𝐻⃗            (B) 𝑆 = 𝐸⃗ × 𝐵⃗            (C) 𝑆 = 𝐸⃗/𝐵⃗         (D) 𝑆 = 𝐸⃗/𝐻⃗   Ans:   Poynting vector 𝑆 = (1/ 𝜇) ( 𝐸⃗ × 𝐵⃗ )         If the medium is linear, 𝐻⃗ = 𝐵⃗/𝜇        So,   𝑆 = (1/ 𝜇 )( 𝐸⃗ × 𝜇𝐻⃗ ) = 𝐸⃗ × 𝐻⃗   Q/ 37. For good conductors, skin depth ( 𝛿 ) varies with frequency ( 𝜔 ) as?   (A) 1/ 𝜔             (B) 1/√ 𝜔                   (C) 𝜔 ...