[Charcoal + Potassium Nitrate + Sulphur] when ground together in the right proportion, make … great photos!
Here is a scene from chemistry class.
First, we made charcoal by heating hardwood without oxygen. This produces a lot of smoke, but in the end, all that’s left in the test tube is charcoal sticks.
Second, we ground the charcoal to a powder, and added a some potassium nitrate and sulphur.
Here is a spoonful of the fresh made black powder
Upon touching a hot coal to it, it ignited and combusted with a lot of smoke!
Quite bright! This is a neat photograph (taken with Droid X)
(Proper safety precautions were taken during this class, including fire prevention and eye protection. Do not repeat without appropriate knowledge and safety precautions in place)
Take a look at this FeedBurner feed — lots of info on rubber band guns! View, Enjoy, and Share.
Just an update on the use of our Home School software package… So far, we have entered 216 activities with 462 images/scans across 13 projects, 12 subjects, and 4 students.
Nearly all of the photographs we take are with the Motorola Droid X. Provided you have sufficient light, the quality is very acceptable.
Here is one of the latest activities recorded:
Well, the fun is increasing with Arduino. We hooked up some circuitry which enables a transistor to switch a fairly large 12V load via a very small 5V digital pin on the Arduino board.
This has been a great learning resource: http://www.kpsec.freeuk.com/trancirc.htm
Basically, we have 12V power going through a motor circuit (protected by a signal diode), and then to the collector of a transistor. The emitter of the transister is connected to ground.
Lastly, the Arduino ground is joined with the emitter, and the transistor is switched by a 5V digital output pin on the Arduino board.
Now, just need to find something useful to do!
Ever been to Dolly Sods in West Virginia? It is really nice.
There is a little group of cabins there called Harmans Cabins — see http://www.wvlogcabins.com/
Here are a few pictures…