Final answer:
A diffraction grating has several advantages over a prism in dispersing light for spectral analysis. It disperses light more effectively, produces a continuous spectrum, has less dispersion, and is less affected by material dispersion.
Step-by-step explanation:
The advantages of a diffraction grating over a prism in dispersing light for spectral analysis are:
- A diffraction grating disperses light more effectively. Unlike a prism, which bends light based on its refractive index, a diffraction grating separates light into its various components by causing interference between the light waves passing through its multiple slits or grooves.
- A diffraction grating produces a continuous spectrum. Unlike a prism, which separates light into a series of colors with some overlap, a diffraction grating produces a spectrum with distinct, evenly spaced, and sharp spectral lines without mixing.
- A diffraction grating has less dispersion. The dispersion of a diffraction grating is uniform across the spectrum, whereas prisms disperse different wavelengths of light differently.
- A diffraction grating is less affected by material dispersion. Material dispersion refers to the phenomenon where different wavelengths of light travel at different speeds through a material. Diffraction gratings are less affected by material dispersion compared to prisms, which can introduce additional dispersion due to the refractive properties of the material they are made from.