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Old 10-17-2007
chris_gee chris_gee is offline
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Sounds good. I am not sure about the heavier boat rising further due to momentum and thus falling further. Since it requires a greater mass of water to support it, it will sit lower in the wave if it is supported on less than its waterline length. Consequently it is moving through less distance, and possibly over a greater time if its speed is less.
My physics is rusty but I would think that the force exerted is that required to lift the mass by however much the centre of buoyancy rises, and that distance being less, the velocity and thus momentum are less.
Hence the observation that heavy boats rise and fall less.

As to pitching through cutting through waves, given your assumptions of equal buoyancy forward it follows that the boat with an overhang must have a blunter bow or at least fuller sections forward to match volumes. However in practice it may not.

With wide quarters a modern boat may rise less at the bow to the waves because of the dampening provided by the stern, but as the wave reachs the stern it will rise more and the bow go lower. It seems to me that in a following sea the stern will rise more and hence the bow go down more.

With overhangs much of the pitch will arise initially from the shorter waterline giving a greater angle of pitch, with reduced dampening until the overhangs immerse. Hence the hobbyhorsing.

Just thoughts as I find it of interest although I claim no expertise.
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