Answer Happy

Purpose: Experimentally determine the wavelength of the red light produced by Diode Laser. List of Materials: Optics Bench and Screen, Diode Laser (OS-8525), Single Slit Disk, millimeter scale to cover the screen, and meter stick. Theory: When a beam of light passes through a narrow opening, or slit, there is spreading of light and interference, which is called diffraction. The angle to the minima (dark spots) in the diffraction pattern is given by formula a sino =2. n (n = 1,2,3....) where a-the slit width (m) - angle from the center of the pattern to the nth minimum (1 for the first min, 2 for the second min,... counting from the center out) 2 - the wavelength of the light (m) Since the angles are usually small, it can be assumed that sino -tan From trigonometry tano = y D where y - the distance on the screen from the center of the pattern to the oth minimum D- the distance from the slit to the screen Finally atan 2- n ay Dn (1) 10 D
Procedure: 1. Set up the laser at one end of the optics bench and place Single Slit Disk in its holder about 3 cm in front of the laser. Attach the mm scale to the screen and set the screen up at the other end of the bench. 2. Turn the laser on and select the 0.08 mm slit by rotating the slit disk until the 0.08 mm slit is centered in the slit holder. Adjust the position of the laser beam from left-to-right and up-to-down until beam is centered on the slit. 3. Measure the distance from the slit to the screen (D) Turn off the room lights and measure the positions of the first and second minima in the diffraction pattern (y1 and y2) Repeat the same steps for 0.04 mm and 0.02 mm slits. Fill out the Data Table and calculate 2 of red light for all six measurements. Calculate the average 2 and % error.
(Standard value for the wavelength of the red light is 2 - 690 nm) Data Tables a= atone_ ay n Dn First Minimum (n=1) 1= x mL 2 (m) Slit Width (m) D (m) Yi (m) %error 0.08x10 0.04x10 0.9x10? 9.8m (980) 0.cfm/10.9cm) 1.68102 9.8m (981) 1.60cm) 0.066m 2.8x102m (Hom) 7.1m (2.806/0.028M 31-102H 0.02x103 Second Minimum (n=2) Y? (m) 2 (m) D (m) Slit Width (m) y error 0.08x103 17210²m 1.700 / 0.017 198cm) 9.8m 0.04x103 3.5x16 3.50 cm/0.035 9.8m (98cm) 0.02x10-3 5.600m 10.056 (71cm) 7.1m