Karnataka Board PUCPUC Science 2nd PUC Class 12

In Producing a Pure Spectrum, the Incident Light is Passed Through a Narrow Slit Placed in the Focal Plane of an Achromatic Lens Because a Narrow Slit - Physics

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MCQ
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In producing a pure spectrum, the incident light is passed through a narrow slit placed in the focal plane of an achromatic lens because a narrow slit ___________ .

Options

  • produces less diffraction

  • increases intensity

  • allows only one colour at a time

  • allows a more parallel beam when it passes through the lens

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Solution

allows a more parallel beam when it passes through the lens

 

To produce a pure spectrum, a parallel light beam is required to be incident on the dispersing element. So, the incident light is passed through a narrow slit placed in the focal plane of an achromatic lens.

Concept: Lenses
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Chapter 20: Dispersion and Spectra - MCQ [Page 442]

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HC Verma Class 11, Class 12 Concepts of Physics Vol. 1
Chapter 20 Dispersion and Spectra
MCQ | Q 3 | Page 442

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