Question

when an object falls freely to the ground acceleration is uniform why?

Answer 1

Practically it is acceleration is not uniform.In theory of second level physics, we neglect upthrust caused by air, but practically its acceleration is not just 'g', rather at each instant falling there is a fluctuation in acceleration. Gravitational force due to the earth is not the only force acting on the body,rather the dragging force due to air is also there. If the force is not the same throughout the motion,then acceleration can't ever be uniform while falling.

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