Find the speed of the 2nd-order maxima on the screen

[burgerkin]

Homework Statement

A man holds a light that emits light of wavelength λ. The light beam passes though a pair of slits separated by a distance d, in a screen plate attached to the front of the light beam(double slits experiment). The beam then falls perpendicularly on a screen, getting an interference pattern on it. The man walks straight toward the screen at speed v. The central maximum on the screen is stationary. Find the speed of the 2nd-order maxima on the screen, where m can be very large. (Use variable or symbol )

Homework Equations

y=\lambdaL m / d

The Attempt at a Solution

L changes with v, and y changes with v

so y = \lambda v t m /d

then v 2nd order maximum (m=2) = y' = \lambda v m /d

 

[Redbelly98]

The Attempt at a Solution

L changes with v, and y changes with v

so y = λ v t m /d

then v 2nd order maximum (m=2) = y' = λ v m /d

Your answer looks correct for small angles, even though L is not really equal to v·t.

I am puzzled by this statement:

Find the speed of the 2nd-order maxima on the screen, where m can be very large

For the 2nd-order maxima, m is 2, which is not a large number. Are you sure you typed this part of the question exactly as it was written in the problem statement?