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Is it possible for a floating body to rise further out of the water as the water level rises around it?

What conditions need to be met and what properties does such an object need to have?

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closed as off-topic by Bill N, stafusa, Kyle Kanos, AccidentalFourierTransform, glS Aug 19 '18 at 12:58

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question appears to be about engineering, which is the application of scientific knowledge to construct a solution to solve a specific problem. As such, it is off topic for this site, which deals with the science, whether theoretical or experimental, of how the natural world works. For more information, see this meta post." – Bill N, Kyle Kanos, glS
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    $\begingroup$ If the liquid being added to the water was of higher density, thus increasing the density of the water. $\endgroup$ – Jack M Aug 12 '18 at 23:55
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    $\begingroup$ Are you asking if the volume of water affects the fraction of a floating object above the water? That answer is "no." The fraction is determined by the densities and the strength of the gravitational field. $\endgroup$ – Bill N Aug 13 '18 at 0:53
  • $\begingroup$ @JackM While that is an answer, I'm assuming homogeneity in the type of fluid. Let's assume Water being added to Water. $\endgroup$ – Axoren Aug 13 '18 at 1:01
  • $\begingroup$ @BillN In the case of a generic solid object like a cube, sphere, or cone, I agree that that is the case. However, I'm wondering if there's any type of object which by some property would defy this. An extreme case would be a propelled object that would measure the difference in water level and oppose it two-fold. I'm more wondering if there's a geometric structure or some other property which would similarly oppose the usual phenomenon. $\endgroup$ – Axoren Aug 13 '18 at 1:05
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    $\begingroup$ So your question is not about a passive object, but something with active technology. That's an engineering question, not a physics one. I'm voting to close based on your comments. $\endgroup$ – Bill N Aug 13 '18 at 14:06
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Assuming the floating object has a fixed solid shape, and a fixed weight, it will settle into the water until the weight of water it displaces equals its weight. I don't see any way for that to depend on the depth of the water, assuming the solid does not touch bottom.

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This question reminds me another one: Does an object float more or less with more or less gravity? . In my answer there, I noted that there is another mechanism of floating, used, for example, by water striders, who float using surface tension. For such water striders, if water level rises around them, the acceleration due to gravity $g$ falls (insignificantly:-) ) with altitude, but the surface tension can remain the same, so the water striders would rise further out of the water :-)

Another possibility: if the body floats in a vessel whose horizontal dimensions vary with height, I suspect that capillary action between the body and the walls of the vessel can cause a similar effect, but I have not considered this possibility in detail.

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