A low DC voltage is produced by the thermocouple when the two junctions are at different temperatures. This voltage is referred to as the thermoelectric voltage. This thermoelectric voltage is produced by the temperature gradient along the thermocouple wires.
Re: What's causes the electric shock type pain in a tooth Hi DM69. I'm not a dentist but I'm pretty sure its the erosion of your tooth exposing the pulp, I had the exact same feeling in my tooth before I had it extracted a month ago, so I feel your pain.
Low levels and deficiency of vital minerals like potassium, calcium and phosphate in the body can result in lip tingling, trembling and shuddering. This can also cause similar symptoms like tingling in the tongue, throat, nose and ears. There may be muscle pain in other parts of the body as well.