Saturday, July 10, 2010

Day 7 - Saturday School

Yeah, there's school on Saturdays in India. I thought it would only be a half-day, but it's more like a three-quarters day. The students have 6 periods instead of 8. My mom came back yesterday afternoon, and we've decided we'll use today to really go through every single box and bottle in the science laboratory cabinet. We need to know exactly what we have so we can figure out exactly what we can do.

So we spend the day looking at the prisms and lenses and discovering that we have a periscope and two kaleidoscopes to work with. There's batteries and resistance boxes, ammeters and voltmeters, and a rheostat that obstinately refuses to work for us. The students have been reading about electrolysis since the 6th grade, and the teachers have tried to demo it with test-tubingly explosive results. I wanted to try catching the gases in soap bubbles instead, and lighting the bubbles, which is safer because of the smaller quantities involved, but it is an unfortunate failure. We don't have large electrodes to make lots of big bubbles or tubing to catch the small, dense bubbles we do have. The match just fizzles out at the touch of water. Still, the copper wire we brought, along with  the copper sulfate, sulfuric acid, and zinc metal granules in the cabinet mean we might be able to do some electroplating.

I also spy magnets of various shapes, and as luck would have it, a whole bunch of iron filings stuck to the strongest one. Two compasses to show the direction of the field could come in handy. And then, the most exciting discovery! A color-changing LED! The color seems to change based on the voltage, which is perfect, because we can change it by adding or removing 1.5V cells (batteries) in series. If we connect it to a 9V battery and use the resistance box, we can change the voltage on the LED easily. We have to be careful though, because 9 volts appears to be a bit much for the poor little diode (or diodes? There's three colors, after all). We've only got one and we don't want it to blow out.

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