NEET-XII-Physics

20: dispersion and Spectra

with Solutions -
  • #2
    Can the dispersive power
    ω=μu-μrμ-1be negative? What is the sign of ω if a hollow prism is immersed into water?
    Ans : No, it cannot be negative, as the refractive index for violet light is always greater than that for red light. Also, refractive index is inversely proportional to `` {\lambda }^{2}``. The sign of ω will be positive, as `` \mu `` is still greater than 1 and as `` {\mu }_{v}>{\mu }_{r}``.
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