In the youngs double slit experiment using a monochromatic light of wavelength , the path difference corresponding to any point - Physics - Magnetic Effect of Electric Current and Light

Question

In the youngs double slit experiment using a monochromatic light of
wavelength , the path difference corresponding to any point having
half the peak intensity is

Udbhav Singh · Accepted Answer

Dear Student,
According to Malus's Law
I=4I0Cos2(φ/2)and Acc to question, I=2I02I0=4I0Cos2(φ/2)Cos2(φ/2)=1/2Cos(φ/2) = 1/2φ/2=π/4φ=π/2

Thus, Path Difference
∆x =λ2π×∆φ∆x =λ2π×π2∆x =λ4

Regards

In the youngs double slit experiment using a monochromatic light of wavelength , the path difference corresponding to any point having half the peak intensity is