Question

Question 6 (1 point) Laser light of wavelength 633 nm falls onto a double slit with slit separation 0.132 mm. An interference pattern is observed on a screen 2.20 m away. How far apart are the bright spots on the screen near the middle of the pattern? 1.51 cm 1.33 cm 1.06 cm 1.66 cm 0.960 cm

Answer 1

Fringe width or didstance between bright spot, $\beta$ = ( $\lambda$ D ) /d .....................(1)

where $\lambda$ = 633 nm is wavelength of laser light used , D = 2.20 m is distance between slits and screen         and d = 0.132 mm is the spacing between slits.

$\beta$ = ( 633 $\times$ 10^-9$\times$ 2.2 ) / ( 0.132 $\times$ 10^-3 ) = 1.055 $\times$ 10^-2 m $\approx$ 1.06 cm