Question

why are opaque bodies not called opaque medium?

Answer 1

hey there!

Opaque bodies not called opaque medium beacause they do not allow light to pass through them.

hope this helps!
:)

Answer 2

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Opaque An opaque object is neither transparent (allowing all light to pass through) nor translucent (allowing some light to pass through). When light strikes an interface between two substances, in general some may be reflected, some absorbed, some scattered, and the rest transmitted (also see refraction ).
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In radiative transfer, it describes the absorption and scattering of radiation in a medium, such as a plasma, dielectric, shielding material, glass, etc. An opaque object is neither transparent (allowing all light to pass through) nor translucent (allowing some light to pass through).  
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opaque object not called opaque medium because the object have a microscopic shape , size . But opaque medium  maybe the composition of many opaque object so a opaque bodies not   called opaque medium at some special condition they can use as medium there we can call them but not every time . 
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