Question

in ydse distance between slits is 0.4mm. wavelength of light is 6000 angstrom. interference pattern is seen on a placed at a distance of 100cm. calculate the distance of 2nd dark and 3rd bright fringes from the central fringe?​

Answer 1

Answer:Fringe width is given by B=AD/

dIn the first case,A1 =6000A°

=6000×10-¹⁰mB1=6mm=0.006m=0.006=6

000×10-¹⁰D/d equation (1)

In the second case, the distance betwee

n the slits and the screen is

D/2,B2=4mm=0.004m=0.004=A2×D/2/d

equation (2)Directing equation (2) by (1)

weget

0.004/0.006=A2/2×6000×10-¹⁰A2=0.004

×2×6000×10-¹⁰/0.006A2=48×10-¹⁰/

0.006A2=8000×10-¹⁰A2=8000 A°.

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