Actually, it depends on witch object it is. If the opaque object is brown, then that means the object absorbed most of the colors of the white light and reflects mostly the brown colors.
All the colors that are NOT absorbed by the object.
light
what processes produce the different colors we see in opaque objects
No, that is what opaque means. Light does not go through an opaque object. An object that is translucent will allow light through, but is opaque enough to keep you from seeing clearly through it (think about frosted glass used for bathroom windows). Transparent is "see through".
The basic difference between an opaque and a transparent object is that we can see through the transparent objects while through the opaque objects, we cannot see.
All the colors that are NOT absorbed by the object.
light
It depends on which frequencies are reflected off the object.
If you can't see through an object clearly it is an opaque object.
what processes produce the different colors we see in opaque objects
No, that is what opaque means. Light does not go through an opaque object. An object that is translucent will allow light through, but is opaque enough to keep you from seeing clearly through it (think about frosted glass used for bathroom windows). Transparent is "see through".