Monday, June 14, 2010
Report done!
I've already written my report... Phew... Now I am just adding pictures to it. Such a great relief.
Saturday, June 12, 2010
Last two set of data
The last two sets of data are in the table inserted into this entry. I just got it! But it was really hard work tried to hold up the pieces of glass while trying to measure the UV with the other hand. I had to go downstairs and into the backyard because at this time the sun doesn't reach our balcony anymore.
But all the hardwork has finally come to mean something: the trend in this last two sets are almost exactly as I thought they would be. The lowest percentage of UV through the glass (i.e. the 15mm thickness) is around the 60's. It is interesting, isn't it? Two light sources resulting in two different trends. I think it is because of the different wavelengths the two carries - the halogen lamp has got to produce longer wavelengths than the sunlight (or otherwise I would be very sunburnt considering the number of hours I spend under the lamp). I am still not too sure whether the more energy a wave carries (i.e. the shorter its wavelength) the more penetrative it is. X ray and gamma ray are shorter than UV and are more penetrative (I think), but then UVA is more penetrative than UVB (that I have gotten from my research). So there mightn't be a definite patter in the matter. Anyway, that's what I got to find out in my research this afternoon! Once I finish the discussion (mind you, it is suggested to be 3-4 pages), all I got to do is to insert pictures and diagrams (which I assume would be easier than writing the actual report).
Best luck to me!!
Some little notes
I've finally got a sunny weekend to finish my experiment. The sunlight looks really strong (and very bright too, I wouldn't go outside without a hat had I not known the UV reading) and I went for a testing. But it turns about to be just about ranging from 1 to 3. Thus it seems rather unstable (just seems) and without a precise nude reading I cannot calculate the percentage of UV that goes through the glass. So I decide to wait a little and the sunlight should register around 3 at noon (the first day the sunlight was 3, and it was only 10 o'clock with some cloud cover). By then the experiment should be good.
I really should do this experiment during summer for the best results. The sunshine now is not so strong. But since Sydney has a low altitude, I guess summer would not help that much anyways. Ah, how I hope at this moment that I live on the top of mount Everest (the higher you go, the stronger the UV).
I really should do this experiment during summer for the best results. The sunshine now is not so strong. But since Sydney has a low altitude, I guess summer would not help that much anyways. Ah, how I hope at this moment that I live on the top of mount Everest (the higher you go, the stronger the UV).
Thursday, June 10, 2010
SRP Researches
Oh god. The SRP is due like in six days time! And I've only just finished the basic draft for my introduction (Ms. Zhang said that we have to reference every sentence even if the whole paragraph comes from one source, so I have a lot more referencing to do). But I guess most of the research has been done by now (unless you count the occational add ins to the discussion).
The most sensational bit was that I actually discovered that the type of lamp I used for the experiment is called halogen lamp (because it is filled with halogen gases like chlorine etc. and not the argon and hydrogen mixture -?- you get in a regular incandescent bulb. It is more efficient). And there are many sources that confirm the fact that it does produce light shifted to the blue end of the spectrum (so it produces UV of the larger wavelengths). This was really important for me as I was at one stage doubting the accuracy of my apparatus. I just randomly gave it a shot at the lamp (to be honest, I didn't expect any UV index other than 0). When it says that the lamp produces UV, I doubted that maybe it was just picking up the brightness of the light (in that case, the apparatus cannot measure the actual amount of UV, but only the brightness of sunlight - which in a way can also tell you how strong the UV is. But that would mean my experiment is stuffed. I know the label says it measures UV, but it was bought on internet - can't be too careful!). But now it turns out that I was just worrying for nothing, so, phew....
I've just been realising that I would need two more sets of data gathered under the sun for my experiment to be better. When I drew up a scatter graph using my results, I discovered that the three sets of data collected under the lamplight has a linear trend that goes straight down. Its lowest point (i.e. when the glass thickness equals to 15mm) is around 28 or so. But the set of data collected under the sun (which was the first set that I did) has its lowest point at around 60. And its general trend was to decrease sharply then the gradient was becoming very slight. So I just want to see if any other data collected under the sun would be like that - if they are going to be, it might be due to the different wavelengths of UV each light source produces (the halogen lamp mainly produces UVA that is just off the violet end of visual spectrum where as the sunlight we get here contain UVB as well. Soda lime glass would absorb the shorter wavelengths, which might be why there is a difference in data. Or it could be that since the sunlight experiment was my first, maybe I didn't handle the apparatus correctly? I don't know, but it's exciting to see the results come up). I need a weekend to do it, because it is only around noon when the UV is the strongest (a research proven fact) - so that the results can be scaled enough to be analysed, otherwise it would be just a whole bunch of zeroes that can tell me nothing.
I don't know what I have put onto the final blog. But Ms Zhang just said to update, so that part has already been taken care of. Hopefully I can finish the report before Sunday (so that I get one day to have fun... oh no! I still have to study for the rotation test and prepare the English and History assessments!! I just hope that term 2 ends as soon as possible) and I've planned to hand it in on Wedensday because I don't want to get deductions simply because the train was late or I sleeped in or an alien took my paper on the way to school.
The most sensational bit was that I actually discovered that the type of lamp I used for the experiment is called halogen lamp (because it is filled with halogen gases like chlorine etc. and not the argon and hydrogen mixture -?- you get in a regular incandescent bulb. It is more efficient). And there are many sources that confirm the fact that it does produce light shifted to the blue end of the spectrum (so it produces UV of the larger wavelengths). This was really important for me as I was at one stage doubting the accuracy of my apparatus. I just randomly gave it a shot at the lamp (to be honest, I didn't expect any UV index other than 0). When it says that the lamp produces UV, I doubted that maybe it was just picking up the brightness of the light (in that case, the apparatus cannot measure the actual amount of UV, but only the brightness of sunlight - which in a way can also tell you how strong the UV is. But that would mean my experiment is stuffed. I know the label says it measures UV, but it was bought on internet - can't be too careful!). But now it turns out that I was just worrying for nothing, so, phew....
I've just been realising that I would need two more sets of data gathered under the sun for my experiment to be better. When I drew up a scatter graph using my results, I discovered that the three sets of data collected under the lamplight has a linear trend that goes straight down. Its lowest point (i.e. when the glass thickness equals to 15mm) is around 28 or so. But the set of data collected under the sun (which was the first set that I did) has its lowest point at around 60. And its general trend was to decrease sharply then the gradient was becoming very slight. So I just want to see if any other data collected under the sun would be like that - if they are going to be, it might be due to the different wavelengths of UV each light source produces (the halogen lamp mainly produces UVA that is just off the violet end of visual spectrum where as the sunlight we get here contain UVB as well. Soda lime glass would absorb the shorter wavelengths, which might be why there is a difference in data. Or it could be that since the sunlight experiment was my first, maybe I didn't handle the apparatus correctly? I don't know, but it's exciting to see the results come up). I need a weekend to do it, because it is only around noon when the UV is the strongest (a research proven fact) - so that the results can be scaled enough to be analysed, otherwise it would be just a whole bunch of zeroes that can tell me nothing.
I don't know what I have put onto the final blog. But Ms Zhang just said to update, so that part has already been taken care of. Hopefully I can finish the report before Sunday (so that I get one day to have fun... oh no! I still have to study for the rotation test and prepare the English and History assessments!! I just hope that term 2 ends as soon as possible) and I've planned to hand it in on Wedensday because I don't want to get deductions simply because the train was late or I sleeped in or an alien took my paper on the way to school.
Sunday, June 6, 2010
Data
Sorry, it has taken longer than expected to get all the data assembled and put into tables. I wanted to do a graph, but then the Excel somehow drew two lines instead of one - so I have to wait for my Mom's assistance. So that will take a while. The data seems not so linear when I draw it out - I suppose that is partly because the apparatus is not very sensitive and that the experiment needs more trials. But however inaccurate it may be, the data still illustrates my point that the thicker the glass is, the less UV gets through. So I suppose that would be alright.
The SRP is due so soon! I am so scared.
Thursday, June 3, 2010
Epiphany!! (did I spell it correctly?)
Well, as far as the data collecting goes - not very well. I find that I would need an exceedingly sunny day in order to get a UV reading that is significant enough to create useful comparisons between the reading taken in the sun and the reading taken behind the glass. Unfortunately these past couple of weeks have all been very cloudy and rainy, so my experiment was impossible to be conducted. I confess that I did not foreseen this development (Sydney seems to be always sunny when my apparatus was still in China, and I dare say that it will continue to be sunny once all the SRP reports have been handed in). So I was incredibly stressed for a couple of days (while secretly relieved that I have an legitimate reason of doing something else). BUT... I finally found a way around this problem!
You see, sometime last week I was wandering around, hoping that my UV metre might pick up some radiation from the lukewarm sunlight. I flipped on my lamp in order to record any possible findings. And guess what? The light coming out of the lamp had a UV measure of 1! (on a partially sunny day - like the day when I took my first set of data - it is about 3) That struck me immediately as an alternate source of ultraviolet radiation. Then I unscrewed the glass covering on the lamp (because from my experiment and researches I know that the glass would make a difference), and the UV read somewhere between 2 and 3. So then I was able to continue my experiment (not to mention that I had to sit in a uncomfortable position for many minutes, doing my experiment under the constant interferencing of my little sister and complaints from my parents). And I got 2 other sets of data. Yay! Now I'm finally done with the experiment (I could wait for a sunny day and record the readings just to make the data more accurate, but I won't count on that too much), I can proceed with researches etc.
The report is due like 2 weeks from now!! And I've only done like half the research for my introduction! And I have lots of other homeworks too and am really stressed. So I'll hope that I can just somehow magically finish this report and would be blessed to never see it again.
I'll post the data onto the next blog after I do all the tables (seriously, the word processing function on the blog is so shabbily poor).
You see, sometime last week I was wandering around, hoping that my UV metre might pick up some radiation from the lukewarm sunlight. I flipped on my lamp in order to record any possible findings. And guess what? The light coming out of the lamp had a UV measure of 1! (on a partially sunny day - like the day when I took my first set of data - it is about 3) That struck me immediately as an alternate source of ultraviolet radiation. Then I unscrewed the glass covering on the lamp (because from my experiment and researches I know that the glass would make a difference), and the UV read somewhere between 2 and 3. So then I was able to continue my experiment (not to mention that I had to sit in a uncomfortable position for many minutes, doing my experiment under the constant interferencing of my little sister and complaints from my parents). And I got 2 other sets of data. Yay! Now I'm finally done with the experiment (I could wait for a sunny day and record the readings just to make the data more accurate, but I won't count on that too much), I can proceed with researches etc.
The report is due like 2 weeks from now!! And I've only done like half the research for my introduction! And I have lots of other homeworks too and am really stressed. So I'll hope that I can just somehow magically finish this report and would be blessed to never see it again.
I'll post the data onto the next blog after I do all the tables (seriously, the word processing function on the blog is so shabbily poor).
Sunday, May 16, 2010
First set of raw data
A close up of the UV-meter. It was indoors at the time, so the measurement reads zero.
The measurement with two layers of glass
The measurement with all five layers of glass
Table of DataI got my UV-meter on the 12th! Much obliged to my mom’s friend (although I had some complaints about her not coming back earlier… I apologize for that here); I will write her down in my acknowledgments if she gives me permission to do so. It is quite small actually, and shuts down by itself after 2 minutes. But I am very happy as it actually works despite its, well, appearance. There is an oval patch underneath the screen that looks like those solar electric battery things. And I guess that is how it detects the UV radiation. Anyway, the photo of the UV-meter will on the blog so that what I am talking about will be clearer.
I just took some measurements of the UV at 10:25, when the weather was sunny with around 10%-20% cloud cover over the horizon. The UV radiation level from my balcony is 3 on the apparatus. And through 15mm of glass it is around 1-2; and if the glass thickness decreases, the UV would increase. I set up the glass on a boiling pan (is that the right name?) with the biggest piece on the bottom. So I just have to stick the UV-meter underneath the glass and add glass pieces on the top to achieve the different thicknesses. It is very convenient and fast: in the beginning I was holding the glasses on one hand and the trying to measure with the other, and if I am doing multiple pieces the glass keeps falling down (coming to think of it that was pretty dangerous as the glass pieces are scraps and the edges are fairly sharp). So, anyway, from the present data my hypothesis seems to be supported. The table of date and my set up pictures are appended above. The decimal readings such as 1.5 mean that the UV reading is changing between two numbers, like 1 and 2.
It is so good to be finally doing the experiment after so many weeks thinking about it. It is turning cloudy now, I can’t seem any direct sunshine from where I am. I need to take measurements on a cloudy day too (multiple samples always make the results more accurate, right?). So I might do it this afternoon or next week (the weather forecast said that it is going to be cloudy and raining most of the time then).
I just took some measurements of the UV at 10:25, when the weather was sunny with around 10%-20% cloud cover over the horizon. The UV radiation level from my balcony is 3 on the apparatus. And through 15mm of glass it is around 1-2; and if the glass thickness decreases, the UV would increase. I set up the glass on a boiling pan (is that the right name?) with the biggest piece on the bottom. So I just have to stick the UV-meter underneath the glass and add glass pieces on the top to achieve the different thicknesses. It is very convenient and fast: in the beginning I was holding the glasses on one hand and the trying to measure with the other, and if I am doing multiple pieces the glass keeps falling down (coming to think of it that was pretty dangerous as the glass pieces are scraps and the edges are fairly sharp). So, anyway, from the present data my hypothesis seems to be supported. The table of date and my set up pictures are appended above. The decimal readings such as 1.5 mean that the UV reading is changing between two numbers, like 1 and 2.
It is so good to be finally doing the experiment after so many weeks thinking about it. It is turning cloudy now, I can’t seem any direct sunshine from where I am. I need to take measurements on a cloudy day too (multiple samples always make the results more accurate, right?). So I might do it this afternoon or next week (the weather forecast said that it is going to be cloudy and raining most of the time then).
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