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JEE Advanced2011PhysicsWaves and SoundActual

Paragraph: A dense collection of equal number of electrons and positive ions is called neutral plasma. Certain solids containing fixed positive ions surrounded by free electrons can be treated as neutral plasma. Let N be the number density of free electrons, each of mass m . When the electrons are subjected to an electric field, they are displaced relatively away from the heavy positive ions.If the electric field bec

Options

  1. A800 ~nm
  2. B600 ~nm
  3. C300 ~nm
  4. D200 ~nm

Correct answer

B. 600 ~nm

Step-by-step solution

gathered =2 f= 2 c = 2 c = 2 c N e^2 / m ₀ gathered Substituting the values, we get =600 ~nm Correct option is (b). Analysis of Question (i) Paragraph does not make the solution very clear. (ii) Solution is simple but based on error and trial method.

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