Which statement describes what thermography primarily measures?

• A. Temperature by detecting infrared radiation from objects
• B. Color features of the scene
• C. Acoustic emissions
• D. Magnetic fields

Answer: (A)

Thermography measures temperature by detecting infrared radiation emitted by objects. An infrared camera senses this radiant energy and converts it into a temperature map, since hotter areas emit more infrared energy than cooler ones. This non-contact method works because all objects above absolute zero give off infrared radiation, with the detected amount influenced by factors like emissivity and distance. The colors in a thermographic image are simply a visual scale representing temperature, not the true visible colors of the scene. The other choices refer to aspects that aren’t thermography (visible color features, sound, or magnetic fields).