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प्रश्न
The free fall of an object is possible only in ______.
विकल्प
air
vacuum
on the surface of earth.
None of these.
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उत्तर
The free fall of an object is possible only in vacuum.
Explanation:
In air an object also feels drag, so its motion is not governed solely by gravity and is not true free fall. Only in a vacuum (no air) does an object accelerate under gravity alone, making the motion free fall.
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