Question

a stone and feather are thrown from a tower both the object show reach the ground at same time but it does not why?

Answer 1

Because of the gravitational force acting on them is equal

Answer 2

According to galileo's law, the feather and and stone should reach the ground at same time but it is possible only in vacuum otherwise this law is disobeyed due to air resistance.
No resistance is offered in vacuum.
Hence the law is obeyed.

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