A light of wavelength 500 nm is incident on a young's slit. The distance between slits annd screen is D=1.8m and distance between slits is d=0.4 mm. if screen moves with s speed 4m/s, with what speed first maxima will move?

Options

A. a. 5mm/s
B. b.4mm/s
C. c.3mm/s
D. d.2mm/s

Answer

A

Explanation

`beta=(lamdaD)?(d)`
Differentiate both size
`(dbeta)/(dt)=(lamda)/(d)(dD)/(dt)`
`V_(B)=(500xx10^(-9))/(4xx10^(-4))xx4`
`=5xx10^(-3)m//s=5m m//s`