Tension
A pulling force along a length of something. A rope has tension when someone is pulling on both ends. Engineers have to make sure things under tension — cables, chains, bridge supports — can handle the load without snapping.
Thermal
To do with heat. A thermal camera is a camera that 'sees' heat instead of light. Thermal imaging lets engineers see which parts of a machine — or a mountain — are getting hotter than they should be.
Thermal Wand
A handheld BFOE tool for reading how hot a rock, vent, or piece of equipment is. Real volcanologists use similar instruments called infrared thermometers — they let you take a temperature without touching the...
Tremor
A small, shaky movement in the ground. Tremors are smaller than earthquakes, but they still matter: at a volcano, a pattern of tiny tremors often means magma is moving underneath.