Recent content by wachovia

I already knew this kind of process, it's done by the chemical process. I want to adapt the idea to put a led that fires a red light when the product becames out of date. Thats why I need a small circuit with a timer .

its better explain the real problem of the project: Imagine a Coca-Cola bottle. It has a validity period! The led will turn red when this period expires ;-) That's why i really need the smallest possible circuit. Suggestions?

Hi there, I'm a material's design student and I have an idea to a project.. This idea needs an electrical circuit , with a led and a timer, but it has to be really really small, because it is for small objects. How can I mount this type of circuit, with a timer that will fire a red light...

there's's not missing the a4 and also the respective d ? I tried your formula (without the third pressure and x,y position) and its not working, it gaves me a big value (1824347.62).. I don't know why! a1=1018 a2=1018 a3=1018 x2=40.2 x3=40.9 y2=-8.55 y3=-8.65

Its not a true solution. If I have, for example three points from North to south, with pressures p1=1020 ; p2=1017 and p3=1013. And if I'm in a position that is at south of p3, there, air pressure must be smaller then p3, but with your formula, I have a value near 1014 or 1015.. That's not...

The air pressure has a decrease variaton from north to south. If I have three points, aligned from north to south with Pressures : p1=1020hPa ; p2=1017hPa ; p3=1013hPa and a point P, who's at south of the point 3, the pressure in P must be smaller then p3 (1013hPa). Can your fomula present...

What is x and y ? decimal latitude and longitude? Or can D be the distances that I'v already calculated?

Absolutly true

, can I use the decimal values of latitude and longitude to x and y ? Or should I convert them to another value?

Hi there, I have a peculiar question. Imagine that you are in a Earth position, obtained by google, that gives you the latitude and longitude. Those values are given in the decimal notation (ex: lat=20.44 ; long=-8.5). Now imagine that you want to know the air pressure in your position...