In the eye of a person suffering from hypermetropia (farsightedness),where is the image of a nearby object formed?

In the dispersion of white light by a prism,which color of light undergoes the maximum deviation?

The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light

Accommodation means the adjustment of light going into the eye for image formation.

Why does the clear sky appear blue? How would the sky appear in the absence of Earth's atmosphere?

$A$ person is able to see objects clearly only when these are lying at distances between $50 \text{ cm}$ and $300 \text{ cm}$ from his eye. Identify the kind of defects of vision he is suffering from. Give reason for your answer.