why wave with lower frequency produce heat? plz explain to me
that's not necessarily true, consider a microwave oven or even higher frequency, infra-red radiation
so please elaborate on what specifically you are referring to ?
In my book, it says we can use a blackened thermometer to detect the radiation just outside the red end of the visible spectrum. I don't understand why only fluorescent materials can detect radiation just outside the violet end of the visible spectrum but not blackened thermometer just like the waves with lower frequency. i.e. why won't the energy in higher frequency waves releases as heat
You can use a blackened thermometer to detect ultraviolet radiation too. A blackbody absorbs all incoming radiation, regardless of wavelength and then emits blackbody radiation characteristic of its temperature.
A blackened thermometer won't distinguish between infrared or ultraviolet.
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