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Finding Drag(for water) 
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#1
Aug914, 01:40 AM

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Correct me if I'm wrong but to find drag for water you have to use this equation:
0.5 * velocity^2 * water density which is 1000kg/m^3 * Drag Coefficient * Cross Sectional Area Velocity is supposed to be in m/s right? not km/h? Okay so for example if there was an imaginary planet with no air and atmosphere, but only a large body of water(ocean). If a 1*1*1 meter cube was falling and it hit the ocean at 200m/s, the drag will be: 0.5 * 100m/s * 1000kg/m^3 * about 1 * 1m^2 = 50000 when it hits the water If the cube is made out of really strong light weight material, wouldn't the cube get flung up? For example if the cube is only a gram. Is this even possible? When I think about it in my head, no matter how hard an object hits the surface of water, it would never bounce that much... So anyways, i feel like I am misunderstanding something... Can someone help me? 


#2
Aug914, 09:43 AM

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#3
Aug914, 12:14 PM

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#4
Aug914, 12:20 PM

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Finding Drag(for water)
Force in what direction? You were asking about drag. That will be directed opposite to the velocity. In order to have a force upward to "fling" the cube upward the velocity must be downward. But as in order to go "upward" the velocity would have to change from downward to upward so must, at some point, be 0. As soon as that is true, there is no longer any drag force.



#5
Aug914, 02:48 PM

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