When something appears blue, it is absorbing all colors except yellow red blue green orange?

All colors are absorbed except blue.

Explanation:

When a beam of light touches a colored object, a part of that beam is reflected while the rest is absorbed by the object. In this way we can only see the color corresponding to the reflected frequency. This means that the color of an object is precisely the color (or colors) that the object “does not have”, that is, it has not absorbed. When we see the color of an object, we are only seeing the color of the part of the light that is reflected by the object in question.

That is, when we illuminate an object of blue color, this object absorbs all colors except blue light. Since it is not absorbed, blue light is reflected in all directions (diffusely) making the object blue.

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