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प्रश्न
What is the difference between Fresnel and Fraunhofer diffraction?
उत्तर
| No. | Fresnel diffraction | Fraunhofer diffraction |
| i. | The Source of light and screen is kept at a finite distance. | The Source of light and screen is at infinite distance. |
| ii. | Spherical or cylindrical wavefronts are considered. | Only plane wavefronts are considered. |
| iii. | It is observed in straight edge, narrow slit, etc. | It is observed in the single slit, double slit, etc. |
| iv. | Lenses are not used. | Convex lenses are used. |
संबंधित प्रश्न
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`[cos60^circ = sin30^circ 1/2]`
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