Here is the problem which I am struggling on, please help me, and solve the given part of problem:
Problem: Coherent light from a sodium-vapor lamp is passed through a filter that blocks everything except for light of a single wavelength. It then falls on two slits separated by 0.510mm. In the resulting interference pattern on a screen 2.30m away, adjacent bright fringes are separated by 2.74 mm.
Part I: What is the wavelength of the light that falls on the slits?
__________nm