First Blog Submission

Experiment Idea
The experiment will be investigating whether the thickness of glass will affect the amount of ultraviolet radiation passing through it. From my research, glass does block part of the UV in the sunlight and thickness is a factor. Glass of same composition but different thickness will be set up under the sun with a UV detector underneath it to record the differences. Glass should be obtained easily and since the experiment does not require much, the cost should not be high. And the glass will be a dome or a box shape to ensure the complete covering of the tested object – to prevent the changing angle of sunlight throughout the day making a difference on the results. If a UV detector cannot be found in shops (which, I think, will happen; because I cannot recall seeing any UV detectors in shops), I will put pieces of colored paper under each glass shade to test UV radiation. Also from my research, UV radiation stimulates certain chemical reaction in dyes that makes them fade or change color. Thus, the piece of paper that receives the least radiation will retain most of its color and a conclusion can be made. I can borrow the shades of color books in paint shops to further compare the colors of the paper pieces if the difference is hard to be distinguished.

But if using the paper pieces, the experiment time will be a lot longer than if I had a detector; I will use multiple samples all at one time to save time running the experiment. This experiment is easily controlled and should not be too hard to conduct.

Variables
Independent – thickness of glass shading the paper pieces

Dependent – the amount of fading in each piece of paper

Controlled:
- The glass quality, i.e. composition, chemicals, coatings etc.
- The capacity of the glass box/domes – just to be fair
- The time the papers are exposed to sunlight
- The place the papers are placed – has to have similar sun exposure
- The type of papers
- The color of the papers – certain shades of color (such as black) absorb more energy from sun, so difference in color might alter the results
- The area of the papers