Experiment 11: CD Diffraction

PURPOSE: Determine the distances between the grooves of a CD to determine if the CD will actually work by comparing to the actual manufactures standard value.

PROCEDURE:

Setup of apparatus to find the wavelength of the red laser beam. d is given as 0.001m/500lines.

Measurement of Ybright 

Using CD diffraction to find the length of the grooves on the disc by measuring the YBright

DATA AND ANALYSIS

Data measurement for the wavelength of the laser.

Calculation for the CD groove or distance, d. 

The actual and standard for all groove distances is 1600nm. Based on the experimental data, the experimental value of d with uncertainty falls within the actual value. 

CONCLUSION:

Based on the experiment, the CD can be confirmed to having the same amount of grooves as the standard CD, but there may be a possibility that the some of the grooves have been altered and scratched and prevents the CD from making the proper sound. The value of the d, gave us the distance between the grooves of the CD that helped defract the laser beam onto the screen. Using the formula and the measured wavelength of the laser which may have some probable.