posted by sara on .
A sodium-vapour lamp illuminates, with monochromatic yellow light, two narrow slits that are 1.00 mm apart. if the viewing screen is 1.00m from the slits and the distance from the central bright line to the next bright line is 0.589 mm, what is the wavelength of the light?
can someone please explain the question to me??
Refer to the double-slit diffraction experiment. There are actually two wavelengths in a sodium lamp, but they are close together and the average wavelength is 589.3 nm. That should be your answer.
Uses the equation that relates the separation of the central bright line and the first fringe to (wavelength)/(slit separation) ratio times the viewing screen distance.
For more about the physics, read this: