Science Buddies: "Ask an Expert"

Hello.
I am a tenth grader and I want to participate in the google science fair 2013. I have quite a few ideas, all of them rather abstract and impractical, but which I can adapt for the fair.
The first thing I thought of was an invisibility 'cloak'. It uses lenses to bend light around objects. I asked my physics teacher if it could work and he sees no immediate pitfalls. Presumably parallel light from a source is first converged, made parallel by diverging it by the same power. Now that the beams are closer together, effectively occupying less space, they are passed through a small black tube. This is done because in practical cases, light will never all be parallel. So the "stray rays" are absorbed by black. The objects to be concealed are placed around the tube. At the end of this tube, rays are diverged and then converged so that they are projected as they originally were. Thus the object is invisible from one point of view. I'm not sure how readable that explanation was.
The problem is, I can't think how this is socially relevant (as i suppose the ideas are supposed to be). I do think I can do this practically, though, if I can only get permission to use the school physics lab, which is really difficult.
Then I thought of a floating island - farm. This would augment food production, so it would be very useful.
This idea has to be researched more. Taking a hollow 'box' like structure inverted on water (the hollow is filled with air, so it floats), the top is covered with a medium like soil, on which crops are grown. The top of the container is permeable. water evaporates everyday from the sea, irrigating the land. Fertilizers are added to restore soil minerals. Evaporation for irrigation is controlled by a mirror apparatus, the angle of which is controlled a bit like in heliotropic plants. I'd use osmosis to increase water levels and prop the mirror up. I'll need a paragraph or a picture to explain that properly, so I think I'll drop it for now.
I suppose I could do all these practically on a smaller scale, with sprouts, cotton, a plastic cup, etc.
Using the same principle of concentration of sunlight, I can make a desalination apparatus, again very useful to combat the water shortages in our region (India, Nepal, Srilanka...) while criminally vast amounts of sea water just pass by unused.
Now the simplest idea of all - a green wall. That involves mainly practical work - plant plants on a wall and in a pot. See which grows better. Then I need a wall to devote for the purpose. But it isn't my own idea, unlike the rest (I'm not sure where I read about it - maybe in a newspaper?). It may have already been practiced and researched.
And then again, I have only 38 days left to do everything.
These were my best ideas. Could you please advise me as to which to pursue? This is urgent. I do need to get started!
Thank You.
PS. Do I need to fear plagiarism?

Hello aditi!

First off, I don't think that plagiarism is something that you would need to worry about; as long as you don't copy someone else's abstract/research paper word for word, using an idea that you've heard of shouldn't be a problem.

I guess I'll go through your ideas one by one, then?

The first- an "invisibility cloak" does seem to be conceptually sound, from what you've said; however, my instincts say that you may run into some technical issues with the light scattering or not diverging/converging correctly. Though it would be really cool, I'm not sure if it would be a good idea to try to finish it before the fair.

The second sounds intriguing; if you can think of a way to model it with paper cups and sprouts on a small scale, go for it! If it works even a little, you can talk about the feasibility of a larger farm to the judges. Desalination, though, is something of an old problem, and you'd have to think of an original solution- maybe try researching what's been tried already? If you can think of one, though, I'd recommend this idea, as it seems to be the simplest and quickest to set up and test with only 38 days left.

For the green wall, would you be testing the relative amounts of growth of plants in a green wall and in pots? This could also work. The only thing is that you'd have to get plants that grow quickly; usually green walls are cultivated over a number of months.

So in summary, I'd recommend doing either the floating farm or distillation. Try brainstorming specific ideas and procedures for both, and make sure the project has a question and purpose, with some idea or concept to test. Then choose one, based on which seems more feasible.

Good luck, and hope this helped! If you have any more questions, don't hesitate to ask.

Thanks a lot for the helpful opinion. I have decided on the floating farm idea.
How do I post an image I have made (on paint)?
I intend to do the experiment with some vessels and sprouts.
I scrapped the mirror system because it was far too complicated to do practically.
The only pitfall, I'm afraid, is that maximum transpiration takes place at midday in the overhead sun. Maximum evaporation (as used for irrigation) takes place at the same time. But the plant would block the overhead, perpendicular sunlight from reaching the evaporation area, which is directly underneath them. So they would receive insufficient water.
I was considering the viability of using a solar cooker to increase the sunlight received by the water to be evaporated. A funnel plan seemed good. I'm just afraid of cooking the plants in the process!
I plan to have three experiments - one set of plants normally grown in a pot, the other as planned with the vessels without the solar cooker, and one with the solar cooker.
Any suggestions or solutions would be greatly appreciated.
Thanks.

Hello aditi,

When posting you will find a tab labeled "Upload attachment" below the typing area. You can upload an image and place it in your post. I'm not sure which formats are supported, but I have uploaded a .pdf file successfully.

WW

Thanks. I really need to start noticing things!
So here's the diagram.

Hello aditi,

Looks great to me! I don't see any flaws with the design other than the one you've pointed out, as long as you can find a way to keep sufficient water under the farm model.

Though I do have one suggestion- you might want to try having multiple small rafts of each group (pot, no solar cooker, solar cooker) in case something goes wrong with the medium or plants in one, to make sure you'll have adequate data and replication.

Hope this helped!