Question

screen is separate from double slit source at 2.5 m the distance between the two slits is 0.05mm the second order bright fringe (m=5)is 9.5cm from the center line .(a) determine the wavelength of the light.(b) calculate the distance between adjaseet bright fringe

Answer 1

Given

Screen is separated from double slit

D = 2.5m

Distance between two slits ( d) is 0.05 mm

Second order bight fringe is 9.5 cm from center line

Usimh

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

$\implies$

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

$\boxed{ \lambda= {95\times 5 \times 10^{-3}\over 5}}$

$\implies$

(a)

$\boxed { \lambda = 950 nm }$

Distance between adjacent bright fringe

(b)

$\boxed{\Delta y= {\lambda D\over d} = 47.5\times 10^{-3}mm}$