Why is a normal eye not able to see clearly the objects placed closer than 25 cm?
A normal eye is not able to see the objects placed closer than 25 cm clearly because the ciliary muscles of the eyes are unable to contract beyond a certain limit.
Why does the sky appear dark instead of blue to an astronaut?
Why does the Sun appear reddish early in the morning?
Explain why the planets do not twinkle?
Why do stars twinkle?
What happens to the image distance in the eye when we increase the distance of an object from the eye?