CD data track

[deleted-563526]

I do not understand how to do it. Should I shine the laser through the protractor? I am not getting a pattern as shown in the figure. I am using a red laser of wavelength 650 nm.

[norman40]

Hi 6thelements,

I'm assuming that you are working on the project described here:

https://www.sciencebuddies.org/science- ... s-and-dvds

Don't shine the laser through the protractor. The laser should be aimed so that the light hits the CD just in front of the protractor at its center point. The light beam should be slightly in front of the protractor. To see a refraction pattern, the angle of the beam (the incident beam) has to be different from 90 degrees. For example, an incident beam angle of about 70 degrees is shown in the project procedure under “2. Making measurements”.

I hope this helps. Please ask again if you have more questions.

A. Norman