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प्रश्न
A piece of wood is taken deep inside a long column of water and released. It will move up
विकल्प
with a constant upward acceleration
with a decreasing upward acceleration
with a deceleration
with a uniform velocity
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उत्तर
The density of wood is less than that of water.When a piece of wood is immersed deep inside a long column of water and released, it experiences a buoyant force that gives it an upward acceleration. The velocity of wood increases as its motion is accelerated by the buoyant force. However, the viscous drag force acts simultaneously to oppose its upward motion. As a result, the initial acceleration decreases and the wood rises with a decreasing upward acceleration.
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