At P2 the order of the fringe will be maximum
The angular separation between two consecutive bright spots decreases as we move from P1 to P2 along the first quadrant
The total number of fringes produced between P1 and P2 in the first quadrant close to 3000
A dark spot will be formed at the point P2
Given d=1.8×10⁻³m and λ=6×10⁻⁷m
Path difference at point P Δx=S1P−S2P=dsinθ where θ angle is measured from vertical line as shown in figure.
For bright fringe dsinθ=mλ ——— 1
Point P1 is the point of central maxima.
At point P2, path difference (Δx)=d
If P2 is the point of the fringe, then d=mλ ⇒m=d/λ=3000
On differentiating equation (1) dcosθ(Δθ)=(Δm)λ= constant for consecutive bright fringe.
cosθ↓ ⇒ Δθ↑ as θ varies from 0 to π/2
Hence A and C are correct answer.