Diffraction of Light<\/p>\n
Name: ____________________________<\/p>\n
The interference pattern of dark and bright bands produced by light passing through two closely spaced narrow slits can be explained by the addition or superposition of circular wavelets originating from the two slits. The length of the path that each wave travels to a particular spot on the screen determines the phase of the wave at that location. Locations where two waves arrive in phase are the brightest; locations where two waves arrive with different phases are darker; and locations where the waves arrive completely out of phase are dark.<\/p>\n
For bright spots:d sin \u03b8m = m\u03bbm = 0, \u00b11, \u00b12, \u00b13, etc.For dark spots:d sin \u03b8m = (m + \u00bd) \u03bb<\/p>\n
We will study the interference of light in today\u2019s lab.<\/p>\n
Open the simulation: <\/p>\n
https:\/\/ophysics.com\/l5.htmlStep 1: Set the slit distance d equal to 3\u00b5m. The wavelength of the light by default is 400 nm so you see a violet\/blue color light. Change the wavelength of the light to 550 nm. You will notice the light turn green.<\/p>\n
Step 2: Click on the button \u201cShow Interference Pattern\u201d. Now you will see the interference pattern on the screen placed at a distance of 10\u00b5m from the double slits. Notice that the light waves coming from the two slits are in phase when they arrive at the bright spots and are completely out of phase when they arrive at the dark spots. <\/p>\n
Step 3: Calculate the angle for the first order maxima (m = 1) using the equation below for the double slit experiment.<\/p>\n
dsin\u03b8m=m\u03bbRemember that:d = 3\u00b5m = 3 x 10-6 m<\/p>\n
\u03bb = 550 nm = 550 x 10-9 m<\/p>\n
Show all your work below to find the angle \u03b81 for m = 1.<\/p>\n
\u03b81 (theory) = <\/p>\n
Step 4: Calculate the angle for the second order maxima (m = 2) now, for the same d and \u03bb that you used in Step 3 above. Show all your work below.<\/p>\n
\u03b82 (theory) = <\/p>\n
Step 5: Go back to the simulation now, and check the \u201cShow Scale\u201d box and uncheck the \u201cShow Wavefronts\u201d box. On the screen measure the distance y1 from the central bright spot (where 0 is) to the first order maxima.<\/p>\n
y1 = <\/p>\n
The distance to the screen is: L = 10\u00b5m<\/p>\n
Find the angle \u03b81 using the equation below. Show all your work. <\/p>\n
tan\u03b81=y1L\u03b81 (experiment) = <\/p>\n
Step 6: Find the percent error. Show all your work below.<\/p>\n
% error= \u03b81theory-\u03b81(experiment)\u03b81(theory) x 100% error= ______________<\/p>\n
Step 7: Go back to the simulation now, and measure the distance y2 from the central bright spot (where 0 is) to the second order maxima.<\/p>\n
y2 = <\/p>\n
The distance to the screen is still: L = 10\u00b5m<\/p>\n
Find the angle \u03b82 using the equation below. Show all your work. <\/p>\n
tan\u03b82=y2L\u03b82 (experiment) = <\/p>\n
Step 8: Find the percent error. Show all your work below.<\/p>\n
% error= \u03b82theory-\u03b82(experiment)\u03b82(theory) x 100% error= ______________<\/p>\n
Step 9: Using the equation for the double slit experiment, calculate the first order maxima angle \u03b81 for wavelength \u03bb = 700 nm (red) and d = 2\u00b5m assuming L = 10 \u00b5m. Show all your work below.<\/p>\n
dsin\u03b8m=m\u03bb\u03b81 (theory) = <\/p>\n
Step 10: Go back to the simulation now, set the slit distance d = 2\u00b5m and \u03bb = 700 nm. <\/p>\n
Paste a picture (or screenshot) of the simulation in the space below. <\/p>\n
Measure the distance y1 from the central bright spot (where 0 is) to the first order maxima.<\/p>\n
y1 = <\/p>\n
The distance to the screen is: L = 10\u00b5m<\/p>\n
Find the angle \u03b81 using the equation below. Show all your work. <\/p>\n
tan\u03b81=y1L\u03b81 (experiment) = <\/p>\n
Step 11: Find the percent error. Show all your work below.<\/p>\n
% error= \u03b81theory-\u03b81(experiment)\u03b81(theory) x 100% error= ______________<\/p>\n","protected":false},"excerpt":{"rendered":"
Diffraction of Light Name: ____________________________ The interference pattern of dark and bright bands produced by light passing through two closely<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-46446","post","type-post","status-publish","format-standard","hentry"],"yoast_head":"\n