Science Buddies: "Ask an Expert"

I can not seem to figure this out. I am doing a science fair project with an experimental question of "How can diffraction of light be used to measure microscopic data track spacing on a CD and a DVD?" I do NOT know what my hypothesis should be and I don't know what the science concept (example- density, air pressure, etc.) would be.
PLEASE HELP AND PLEASE HURRY!!! It's due soon!

RudyKay2 - I assume you have read through the Science Buddies experiment titled 'Using a Laser Pointer to Measure Data Track Spacing'. It tells in good detail the way that light refraction can be used to measure and calculate the track spacing on CD's or DVD's. Look over the material and if there is something that you have problems understanding, come back to the Experts with specific questions. We want to help, but we can only do that when you have explained what it is that you are having difficulty understanding.

https://www.sciencebuddies.org/science- ... ml#summary

Rick Marz

Thank you for replying, sorry for not making things clear enough. I understand the experiment, but I don't know what the science concept would be. I hope that helps and if it doesn't... try and figure it out.

The science concept is the underlying idea or notion of the project. Your project in particular deals with interference and diffraction, which are actually mentioned under the sub-heading "Terms and Concepts" in the link provided by Rick Marz. Hope that helped!

Another important concept is that light behaves like a wave. (For the sake of accuracy: it can also behave like a particle a times; how it can behave as both a wave and a particle Is the central riddle of quantum mechanics, which some of you may learn much later in your education.)