A piece of paper and a coin both having the same mass are dropped from the 10th floor of a building. The piece of paper would take more time to reach the ground because.

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Q: 11 (NDA-II/2013)
A piece of paper and a coin both having the same mass are dropped from the 10th floor of a building. The piece of paper would take more time to reach the ground because.

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,8,12,7,8,2,3

keywords: 

{'gravitational pull': [0, 0, 2, 1], 'coin': [0, 3, 6, 4], 'paper': [1, 0, 4, 7], 'buoyant force': [0, 0, 0, 1], 'ground': [2, 1, 4, 17], 'same mass': [0, 0, 2, 3], '10th floor': [0, 0, 0, 1], 'building': [1, 0, 2, 6], 'downward direction': [0, 0, 0, 3]}

The correct answer is option 2: buoyant force on the piece of paper is more than that on the coin.

When a piece of paper and a coin are dropped from the same height, the paper takes more time to reach the ground because it experiences a greater upward buoyant force compared to the coin.

Buoyant force is the force exerted by a fluid (in this case, air) on an object immersed in it. It acts in the opposite direction to the weight of the object. The magnitude of the buoyant force depends on the density of the fluid and the volume of the object.

In this scenario, the piece of paper has a larger surface area compared to the coin, which means it displaces a larger volume of air as it falls. Since the density of air is much lower than that of paper, the buoyant force on the paper is relatively higher. This upward buoyant force partially counteracts the downward force of gravity acting on the paper, resulting in a slower descent.

Option 1 is incorrect because the gravitational pull is the same for both the paper and the coin; mass does not affect the gravitational force. Option 3 is incorrect because buoyant force acts in the upward direction, opposing gravity. Option 4 is also incorrect as