MCQ
In Young's double$-$slit experiment, an interference pattern is obtained on a screen by a light of wavelength $6000 \mathring A$, coming from the coherent sources $S_1$ and $S_2$. At certain point $P$ on the screen third dark fringe is formed. Then the path difference $S_1 P-S_2 P$ in microns is
- A$ 0.75$
- ✓$ 1.5$
- C$ 3.0$
- D$ 4.5$