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jamescrosetto
May 10, 2021, 12:28 PM
Can someone help me with this one:

An object that is a good reflector is also a:?
anderssok09
May 11, 2021, 02:51 PM
Can someone help me with this one:

An object that is a good reflector is also a:?

Good emitter
bob152637485
May 27, 2021, 01:31 PM
Good emitter

According to the test, it is actually poor emitter.
rofo42
June 5, 2021, 06:52 AM
According to the test, it is actually poor emitter.

High reflectivity equals low emissivity. I believe the test answer is correct.

Source: ITC fundamentals of thermal science book.
SecondGen
June 13, 2021, 02:18 PM
High reflectivity equals low emissivity. I believe the test answer is correct.

Source: ITC fundamentals of thermal science book.

Correct, highly reflective objects do not emit thermal radiation very well. They reflect infrared light just like visible light so you can easily get false readings, this is why a shiny lug can sometimes look hotter than cable insulation because you are seeing the reflection of other heat sources on the lug. The dull, non-reflective insulation is the more true reading. Bus bar is another good example if you've seen the difference in scanning insulated vs. non-insulated LV gear. You can often times see you own body heat if you stand directly in front of a shiny object you are inspecting. With that said, its still possible to see loose connections on shiny bus, it just takes some adjusting.