Experiment 15
SINGLE-SLIT DIFFRACTION
AND BABINET'S PRINCIPLE

ANALYSIS


1.  Use the diffraction grating data to calculate the wavelength of the laser light. Note that the pair of each order of bright spots provides data for calculating λ. Calculate the value of sin θ for each order using the formula and enter in cells F19:F21. Determine the wavelength λ of the laser light from the value of d in cell D14 and from the values of sin θ in cells F19:21. Enter the average result in cell D42.

2.  Using the wavelength calculated above and the "hair" diffraction patterns, calculate the thickness w of each hair used. Note that each pair of intensity minima will yield a value for the thickness of the hair. Enter these values for w in the tables in cells G28:G31 and G35:G38. These several values from each hair’s diffraction pattern can be averaged. Enter the averaged values in cells D44 and D46.