In a Young's double slit experiment λ=500nm, d=1.0mm and D=1.0m. Find the minimum distance from the central maximum for which the intensity is half of the maximum intensity.
A. 2×10⁻⁴ m
B. 1.25×10⁻⁴ m
C. 4×10⁻⁴ m
D. 2.5×10⁻⁴ m