DIFFRACTION+GRATING

Back to IB PHYSICS > EM WAVES OPTION =DIFFRACTION GRATING=
 * WAVES AND SOURCES || OPTICAL INSTRUMENTS || TWO-SOURCE INTERFERENCE || DIFFRACTION GRATING || X-RAYS || THIN-FILM INTERFERENCE ||
 * Multiple-slit diffraction **

Describe the effect on the double-slit intensity distribution of increasing the number of slits.

MULTIPLE SLIT DIFFRACTION: As the number of slits increases above two, the light and dark pattern becomes more defined; the fringes are brighter; but the angles of the maxima are the same.

DIFFRACTION GRATING: A glass plate with many equally spaced lines eg 600 per mm. Light passing through creates an interference pattern.



Derive the diffraction grating formula for normal incidence.

Outline the use of a diffraction grating to measure wavelengths.

DIFFRACTION SPECTRA: A mixture of light eg white light, can be separated into its constituent colours due to the different angles of interference maxima which depend on the wavelength of the light.

Use of the spectrometer is not included. Solve problems involving a diffraction grating