Question:medium
For an aperture of $5 \times 10^{-3}\,\mathrm{m}$ and a monochromatic light of wavelength $\lambda$, the distance for which ray optics becomes a good approximation is $50\,\mathrm{m}$, then $\lambda =$
For an aperture of $5 \times 10^{-3}\,\mathrm{m}$ and a monochromatic light of wavelength $\lambda$, the distance for which ray optics becomes a good approximation is $50\,\mathrm{m}$, then $\lambda =$
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Fresnel Distance ($Z_F$) defines the boundary between Ray Optics and Wave Optics. For distances $<Z_F$, diffraction effects are negligible (Ray Optics valid).
Updated On: Mar 26, 2026
- $5000\,\mathring{A}$
- $6000\,\mathring{A}$
- $5400\,\mathring{A}$
- $6500\,\mathring{A}$
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The Correct Option is A
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