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प्रश्न
A piece of wood is taken deep inside a long column of water and released. It will move up
पर्याय
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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संबंधित प्रश्न
A solid sphere falls with a terminal velocity of 20 m s−1 in air. If it is allowed to fall in vacuum,
A solid sphere moves at a terminal velocity of 20 m s−1 in air at a place where g = 9.8 m s−2. The sphere is taken in a gravity-free hall having air at the same pressure and pushed down at a speed of 20 m s−1.
(a) Its initial acceleration will be 9.8 m s−2 downward.
(b) It initial acceleration will be 9.8 m s−2 upward.
(c) The magnitude of acceleration will decrease as the time passes.
(d) It will eventually stop
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