Question

how do people come to an understanding that earth is in sperical shape

Answer 1

The idea of the Earth being a flat disc is also inconsistent with the fact that a given lunar eclipse is only visible from half of the Earth at a time. The only shape that casts a round shadow no matter which direction it is pointed is a sphere, and the ancient Greeks deduced that this must mean the Earth is spherical.

Answer 2

Answer:

In olden days people felt that earth is flat because it looks flat . However they had a doubt , if it is flat how does the water in ocean remain there , Why does it not spell out of the earth ? To get clarity they assumed fencing around flat earth . After that 1 ) They assumed shape of earth is round by observing the shadow of earth in lunar eclipse . In every eclipse they found the shape of the earth is in round even though there is a chance of getting linear , elliptical shadows by a circulr object . 2 ) Some sailors who started their journey in ocean , reached the same place after travelling large distance in one direction only . 3 ) Observing ships approaching the port also helped to change their openion about the shape of the earth , that is , usually they see smoke of the ship first and then top of the ship after that the whole ship . 4 ) Observations about the movement of stars . Different stars visible from different places on the earth also helped to think about the shape of the earth . 5 ) In 1969 when man landed on the moon and observed the earth's shape from the moon and it is spherical ......

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