The diagram illustrates an arrangement that has been assembled to show two-source interference. Microwaves with wavelength $\lambda$ travel through two slits $S_1$ and $S_2$. The detector is displaced away from point O in the direction shown by the arrow. The signal received falls until the detector arrives at point X, then rises again once the detector moves past X. Which equation gives the position of X correctly?
- A$OX = \lambda$
- B$OX = \frac{\lambda}{2}$
- C$S_2X - S_1X = \lambda$
- D$S_2X - S_1X = \frac{\lambda}{2}$