Question

IN YOUNG'S DOUBLE SLIT EXPERIMENT WITH A ​MONOCHROMATIC LIGHT OF WAVELENGTH 4000A , THE FRINGE WIDTH IS FOUND TO BE 0.4 mm . WHEN THE SLITS ARE NOW ILLUMINATED WITH A LIGHT OF WAVELENGTH 5000A THE FRINGE WIDTH WILL BE

Answer 1

fringe width in Youngs  double slit experiment
 w = Dλ/d 

slit separation d and screen distance D are kept constant.
   w2 / w1 = λ2 /λ1
   w2 = 0.4 * 5000 / 4000 = 0.5 mm

Answer 2

Answer:

here is your answer mate..