why the image reaches inverted to brain/eye?

Answer:
Once an image passes through the lens in your eyes it is invert by that lens (all lenses have this effect) the image is projected to your retina upside down the optic nerve then relays it to your brain which processor the information and turns the image right way up.

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because our eyes have the properties of mirror that's why everything the eye can see is inverted.

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Because our lenses are convex lenses, thus images reach our retina inverted. Our nerves in the retina translate the images 'reinvertedly' and transmit the signals to our brain, so our brains receive the correct image.

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because it acts as a camera, not easy to explain it without a drawing..-
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picture....-...
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got the point ? :p

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