Two coherent sources of light interfere and produce fringe patterns on a screen. For central maximum, the phase difference between the two waves will be

Step-by-step solution

For central maximum, path difference is zero hence phase difference for coherent sources of light will be zero. And the relation between phase difference and path difference is, ∆ ϕ = 2 π λ ∆ x , where Δ x is path difference and ∆ ϕ is phase difference. So due to zero path difference phase difference is also zero.