Interference fringes are observed on a screen by illuminating two thin slits 1 mm apart with a light source ( λ=632.8 nm ). The distance between the screen and the slits is 100 cm. If a bright fringe is observed on a screen at a distance of 1.27 mm from the central bright fringe, then the path difference between the waves, which are reaching this point from the slits is close to: [Main Sep. 02, 2020 (I)]
(a) 1.27μm
(b) 2.87 nm
(c) 2 nm
(d) 2.05μm