Nearly monochromatic light of wavelength 420 nm is split in two beams. the first beam traveled 105 nm to the screen more than the second beam, thus yielding a path difference of 105 nm. a) calculate the phase difference between the two beams. the interference pattern of the two beams will be (a) destructive (b) constructive (c) more information is needed

phase difference = π / 2

constructive interference

Explanation:

Given data

wavelength = 420 nm

1st beam = 105 nm

path difference = 105 nm

to find out

phase difference  and interference pattern of the two beams

solution

we use here equation of phase difference that is

phase difference = 2π / wavelength × Δx

put here value

phase difference = 2π / 420 × 105

phase difference = π / 2

and

we know that  here path difference Δx is the integral multiple of the wavelength  so it will be constructive interference

Δx is wavelength / 4