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Karnataka Board PUCPUC Science Class 11

If the Separation Between the Slits in a Young'Sdouble Slit Experiment is Increased,What Happens to the Fringe-width?If the Separation is Increased Too Much, Will the Fringe Pattern Remain Detectable?

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Question

If the separation between the slits in a Young's double slit experiment is increased, what happens to the fringe-width? If the separation is increased too much, will the fringe pattern remain detectable?

Answer in Brief
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Solution

The fringe width in Young's double slit experiment depends on the separation of the slits.

\[\chi = \frac{\lambda D}{d}\]

where

\[\lambda =\text{ wavelength}\]

\[\chi =\text{ fringe width}\]

\[D =\text{ distance between slits and screen}\]

\[d =\text{ separation between slits}\]

On increasing d, fringe width decreases. If the separation is increased too much, the fringes will merge with each other and the fringe pattern won't be detectable.

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Chapter 17: Light Waves - Short Answers [Page 379]

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HC Verma Concepts of Physics Vol. 1 [English] Class 11 and 12
Chapter 17 Light Waves
Short Answers | Q 10 | Page 379

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