The concept of emissivity is important in understanding the infrared emissions of objects. This is a property of a surface that describes how its thermal emissions deviate from the ideal of a black body. To further explain, two objects at the same physical temperature will not show the same infrared image if they have differing emissivity. For example, for any pre-set emissivity value, objects with higher emissivity will appear hotter, and those with a lower emissivity will appear cooler. For that reason, incorrect selection of emissivity will give inaccurate results when using infrared cameras and pyrometers. COUNT 3
QSN1 What is the term for the property that describes how a surface's thermal emissions deviate from the ideal of a black body? ANS1 emissivity QSN2 How will the infrared image of an object with a higher emissivity appear in relation to one with lower emissivity? ANS2 hotter QSN3 Along with pyrometers, what devices can receive inaccurate results if emissivity is not set correctly? ANS3 infrared cameras