Both the wavelength of light and the separation between the slits play important roles in shaping the interference pattern in experiments like the double-slit setup:
- Effect of Wavelength:
- The fringe width (distance between bright or dark fringes) is directly proportional to the wavelength.
- Using light with a longer wavelength (like red) results in wider spaced fringes.
- Using a shorter wavelength (like blue) produces narrower fringes that are closer together.
- Effect of Slit Separation:
- The fringe width is inversely proportional to the distance between the slits.
- When the slits are closer together, the fringes spread out more and appear farther apart.
- When the slits are further apart, the fringes get closer together and become more tightly packed.
So, increasing wavelength or decreasing slit separation makes the interference fringes wider, while decreasing wavelength or increasing slit separation makes them narrower. Both factors together determine the spacing and clarity of the interference pattern.