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प्रश्न
The total energy of an object falling freely towards the ground ______.
विकल्प
decreases
remains unchanged
increases
increases in the beginning and then decreases
उत्तर
The total energy of an object falling freely towards the ground remains unchanged.
Explanation:
In an object falling freely to the ground, as the object's distance from the ground decreases, so does the potential energy stored in the object; But the kinetic energy of a freely falling object increases as the velocity increases over time. Thus, the potential energy lost by an object in free fall is equal to the kinetic energy it gains, i.e. the total energy of the object remains constant.
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