Last Blog Post

Hi. So I'm done. Yay! I have finally done my experiments! Ok, I found my biggest problem from my whole srp was the fact that it was impossible to find the materials for my second experiment, which was testing suncreen spfs. Many of the materials I needed I had to obtain from America. So a month before the project was due, I changed the topic for the last time to testing whether distance affects the light intensity of a point source. It went pretty well, and I had enough times to redo the experiment. Some errors that I came across throughout the experiment was the positioning of the light sensor. What I found was that when I dragged the stand I used in the experiment, 10 centimetres, the stand wasn't in exactly the same position it would have been in previously, it would have moved, a couple of centimetres to the left or to the right. This would have affected the readings as the sensor was taped onto the stand, and would have moved along with it. I would have liked to improve the experiment by using different point sources. Earlier this week, I came across a similar experiment to mine, but instead of using a light globe, it used a directed laser. Interestingly enough, the distance didn't seem to affect the intensity what so ever. It would have been interesting to investigate why different point sources may or may not have been affect by it. Oh well. It's over and done. I'm finished. that's all that matters currently.

Not Happy Jan

Alrighty, Just a bit for today. What is that PASPORT light sensor and a Xplorer GLX I was talking about earlier?

Well according to cider house it :
"Lets your students discover the excitement of science with the new PasPort Xplorer GLX datalogger.

The Xplorer GLX offers state-of-the-art datalogging to get your students involved in data gathering and analysis. A departure from note-taking and tedious set-up, your students can plug in a sensor, press the start button and begin data collecting immediately. It really is that simple!

The new Xplorer allows your students to extend their senses and experience the forces of nature in or out of the classroom."

Special Features....well there's tones...
Use with a computer and take full advantage of our award-winning DataStudio software.
Large 320 x 240 backlit transflective LCD grayscale display. Readable in a dark room as well as sunlight
8 Sensor Ports, including built-in Sound Sensor, Voltage Sensor, and Temperature Sensors (2)
50,000 Hz maximum sampling rate
Real-time graphing and instant calculations from Floating Point Processor (FPU)
10 MB Internal Memory - Useful for high data collection rates and storing multiple data files
Built-in graphing calculator with expression editor
Built-in dual independent function generators
Built-in speaker for sound output
Compatible with all PASPORT Sensors and ScienceWorkshop Sensors (requires analog and digital adapters)

*got this stuff from
http://www.ciderhouse.com.au/glx.html

Gathering from that information, it is much more advanced then my dick smith light sensor : (
View on the top. I've named it....david

Want A piccy of the awsum goliath pasport?

Where here it is:opps...second from the top

GRUMPY

I should totally change my blog format. It's totally misleading. Maybe instead of Science on Sunshine...Starry Science? nah, it takes to long to find a template and stuff like that. I'm pretty bummed actually. My friend told me I'll be at a day in unsw on the SRP hand in day. schmucks...

Okay, on with it. I just came back from Bowen library today, as I needed to research for my experiment. Great books on astronomy. I was also reading the checklist about similar experiments. I've been browsing and I've found a couple
1) instead of using a lux meter, a PASPORT light sensor and a Xplorer GLX was used....Newly found
2) using a laser instead of a bulb...I found that already like couple of weeks back.
3) using a torch instead of a bulb...NF too

So I'll use them to relate with my experiment.
I've gotta start working on it...

Interesting Facts

Yes, I haven't been posting for a long long time : (. but good thing is I've just finished my 8th grade piano exam! yayz! So here is a bunch of info I've been planning to post, but was sitting in my doco folder for 2-ish weeks.

Inverse Square Law... What the...yes sounds weird, but it's the relationship between brightness and distance. Yep, it's got stuff to do with my experiment. Apparently, the law states that the the area in which the light was spread is proportional to the square of the distance. This is why there was such a drastic drop in the light intensity the further the sensor was moved. The light had to spread, so it wasn't so intense in one area...

Okay, next up...the Lux Meter, btw I really don't like Dick Smith. I proclaimed it in Geography. They gave me a lux meter with a dead battery. The only DS i like, eastgardens, of course, replaced it for free! Lucky me...but that's not relevant. The lux meter is a device used to record light intensity. It records stuff in Lux or FC. The light that falls onto the sensor is coverted from light energy to electric energy which calculates an output which is usually shown on video display. Lux meters or light meters are used to measure levels of light in schools, hospitals, production areas, laboratories, and passageways.

Lastly, Stars. My experiment has stuff to do with astronomy, and by measuring light intensity and distance, astronomers can work out the distance of the stars. They do this by investigating the brightness of the stars.

That's all folkies I'll update soon. I hope

Observations

Alrighty. I've just conducted my marvy (georgia Slang) experiment. I did it 4 times to ensure reliability. so here are some pics of the set up:

So the results for the four trials were pretty similar. The intensity was really high at the 10cm interval but once it hit the 20-30cm intervals it dropped drastically. I've been trying to make my table for hours though. I think the excel equivalent for mac, graphs just won't let me insert a line of best fit. It's pretty frustrating...

Method, Variables, aim, hypo etc.....

Ms. Zhang if you are reading this, please know this is not blog 2, blog 2 is further down. I have changed my project since blog two and i put up the method of my new experiment for it.
Hypothesis

My hypothesis stated that the closer the light source, the stronger the light intensity.

Aim

To investigate whether distance effects the intensity of light from a light source.

Risky Assessment
Identify Light bulb
Assess If the light bulb is touched, it may burn the skin.
If the lamp was dropped, the bulb could break
Control Avoid touching the bulb at all times
Dispose Switch off the bulb when the experiment is over to allow it to cool down


Materials
Dick Smith Lux meter
A music stand
Sticky tape
Measuring Tape (at least 2 metres)
lamp with a lightbulb (lightbulb needs to be exposed)
Darkened Room (at least 1 by 2 metres in area)
A pen
A notebook
A computer
Excel(windows) program/Graphs (mac) program

Method
Setting up the equipment
1. An area of 1 by 2 metres was cleared up to conduct the experiment
2. A lamp, with an exposed bulb was connected to a power point and placed on one side of the area.
3. Books were placed under the lamp so the light bulb was 70cm from the ground
4. A music stand was set up directly opposite the lamp
5. The sensor was taped- to prevent movement- onto the bulb at an elevation of 70cm.
6. Measuring tape was positioned directly above the lamp and then taped down with sticky tape.
7. The sensor was positioned horizontally opposite to the light bulb at an interval of 10cm.
8. The lightbulb was then turned on.
9. After the light meter was turned on
10. A measurement was read from behind the stand.
11. Observations were recorded into the log book
12. The stand was pulled back another ten centimetres
13. Steps ten to twelve was repeated until a distance of 2 metres was reached
14. Steps ten to fourteen was repeated another three times to ensure reliability
The average luminosity for each distance was calculated


Controlled Variables
wattage of the lightbulb, the height at which the lamp stood, the height of the music stand, the length of the tape, the darkness of the room and the allocation of the lux meter

The independent variable was the distance between the light source and the sensor and the dependent variable will be the light intensity from the light source.

LUX LUX LUX

One essential equipment i needed to use to conduct my experiment was the lux meter. A Lux meter is used to measure the light intensity of a certain object.