The rotation of Earth on its axis is the reason we have day and night and each day is 24 hours long. If the Earth stopped rotating on its axis, we would no longer have a 24-hour day. In that scenario, we will have 6 months of sunlight and 6 months of darkness and thus, each of our days will be 1 year long. This is due to the fact that, even in the absence of rotation, Earth still goes around the Sun once every 365 (about) days. This would cause extremely hot temperatures on the sunlit side of Earth and extremely cold weather on the dark side of the planet. The vegetation would die as a result and we would find it extremely tough to survive.
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