Question

A viewing screen is separate from double slit source by 1.2m the distance between the two slits is 0.03mm the second order bright fringe (m=2)is 4.5cm from the center line .(a) determine the wavelength of the light.(b) calculate the distance between adjaseet bright fringe

Answer 1

Given some information

Screen is separated from double slit

D = 1.2m

Distance between two slits ( d) is 0.030 mm

Second order bight fringe is 4.5 cm from center line

$\boxed{ y_2= {2\lambda D\over d}}$

$\implies$

$\boxed{ \lambda= {y_2 d\over 2D}}$

$\boxed{ \lambda= {45\times 3 \times 10^{-3}\over 2.4}}$

$\implies$

We get the answer

(a)

$\boxed { \lambda = 562.5nm }$

Distance between adjacent bright fringe

(b)

$\boxed{\Delta y= {\lambda d\over d} = 22.5\times 10^{-3}mm}$