Question

Why does it take some time to see objects in a dim room, when you enter the room from bright sunlight outside?

Answer 1

beacuse in bright light the iris contract and pupil allow less lights rays to enter in the eye
by entering in dim light the eye take time to expand iris and allow to pupil enter more light to the etes

Answer 2

When we remain our eyes get fixed for the wider view as the pupil becomes larger allowing the maximum light to pass through it
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but when we enter the dim room the pupil slowly becomes thin and tries to catch maximum light for the image formation hence it takes some time to see objects in a dim room when we enter the room from bright sunlight outside.