Question

why are Ahmedabad and Kolkata able to see the noon Sun exactly overhead twice a year but not Delhi

Answer 1

Ahmedabad and Kolkata lie in the tropical zone while Delhi is slightly above the tropic of cancer.The two former cities get the sun overhead twice a year.This happens wile the suns rays shifts from the equator to the tropic and secondly when it moves away from the tropic to the equator.However in cities like Dehi which does not lie in the tropical zone it will not receive the noon sun overhead twice a year.

hope that helps you!