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Step 2Viva la resistance!
Or.. the concepts behind what we are doing.
The first thing to understand is the concept of electrical resistance. Our friend Wikipedia defines it as such:
Electrical resistance is a ratio of the degree that an object opposes an electric current through it, measured in Ohms. Its reciprocal quantity is electrical conductance measured in siemens. Assuming a uniform current density, an object's electrical resistance is a function of both its physical geometry and the resistivity of the material it is made from
Facinating.. now wake up..
One useful product of electrical resistance is that when you attempt to pass electricity through a conductor, the resistance generates an amount of thermal energy relative to the resistance and electrical force. In other words, It gets warm. The more electricity you shove through, the hotter it gets. Sometimes it can get hot enough to glow.
One example of this is light bulbs. The filament in the bulb is nothing more than a thin wire made of Tungsten. When you pass current through it, it gets so hot it glows.
Another example is space heaters. Most electric heaters have filaments made of nichrome or ceramic. They use just enough electricity to get the element hot, but not usually enough to glow.
The key to using electrical resistance for heating is to find an element that is conductive, has enough resistance to heat up, but is also thermal resistant, so it will not start on fire or dissolve. Now, normally I would think of Kryptonite or Wonderflonium. But as neither of those are real, and both are freaking out my spell checker, lets turn to a more humble (and cheap) work horse.
Graphite!
The first thing to understand is the concept of electrical resistance. Our friend Wikipedia defines it as such:
Electrical resistance is a ratio of the degree that an object opposes an electric current through it, measured in Ohms. Its reciprocal quantity is electrical conductance measured in siemens. Assuming a uniform current density, an object's electrical resistance is a function of both its physical geometry and the resistivity of the material it is made from
Facinating.. now wake up..
One useful product of electrical resistance is that when you attempt to pass electricity through a conductor, the resistance generates an amount of thermal energy relative to the resistance and electrical force. In other words, It gets warm. The more electricity you shove through, the hotter it gets. Sometimes it can get hot enough to glow.
One example of this is light bulbs. The filament in the bulb is nothing more than a thin wire made of Tungsten. When you pass current through it, it gets so hot it glows.
Another example is space heaters. Most electric heaters have filaments made of nichrome or ceramic. They use just enough electricity to get the element hot, but not usually enough to glow.
The key to using electrical resistance for heating is to find an element that is conductive, has enough resistance to heat up, but is also thermal resistant, so it will not start on fire or dissolve. Now, normally I would think of Kryptonite or Wonderflonium. But as neither of those are real, and both are freaking out my spell checker, lets turn to a more humble (and cheap) work horse.
Graphite!
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en.wikipedia.org/wiki/Jadarite