What is meant by the far point?

The focal length of the eye lens increases when eye muscles

Name the component of white light that deviates the least and the most while passing through a prism.

Sometimes you see a person reading the newspaper by placing it very close to his eyes. Which defect is he suffering from? How can the defect be removed?

Why does the sky appear dark and black to an astronaut instead of blue?

$A$ beam of white light falling on a glass prism gets split up into seven colours marked $1$ to $7$ as shown in the diagram. $A$ student makes the following statements about the spectrum observed on the screen.
$(a)$ The colours at position marked $3$ and $5$ are similar to the colour of the core of a hard-boiled egg and the colour of the sky respectively. Is the statement made by the student correct or incorrect? Justify.
$(b)$ Which of the two positions correspond closely to the colour of $(i)$ a solution of potassium permanganate,$(ii)$ danger or stop signal lights?