Effective refractive index of the ionosphere neff=n0[1−f280.5 N]1/2 where f is the frequency of em waves
This question has Statement-1 and Statement-2. Of the four choices given after the Statements, choose the one that best describes the two Statements.…
JEE Main 2013 — Physics Optics
This question has Statement-1 and Statement-2. Of the four choices given after the Statements, choose the one that best describes the two Statements. Statement-1: Short wave transmission is achieved due to the total internal reflection of the e-m wave from an appropriate height in the ionosphere. Statement-2: Refractive index of a plasma is independent of the frequency of e-m waves.
Held on 22 Apr 2013 · Verified 6 Jul 2026.
Options
- A
Statement-1 is true, Statement- 2 is false.
- B
Statement-1 is false, Statement- 2 is true.
- C
Statement-1 is true, Statement- 2 is true but Statement −2 is not the correct explanation of statement-1.
- D
Statement-1 is true, Statement-2 is true and Statement −2 is the correct explanation of Statement-1.
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