Mathematician solves rowing boat "wiggle" problem
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Mathematician solves rowing boat "wiggle" problem
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Re: Mathematician solves rowing boat "wiggle" problem
#2"to show that the balance of forces in this rig as the oars are pulled through the water"
If the oars are pulled through the water, the boat wouldn't move.
Re: Mathematician solves rowing boat "wiggle" problem
#3"to show that the balance of forces in this rig as the oars are pulled through the water" If the oars are pulled through the water, the boat wouldn't move.
What do you mean?
Re: Mathematician solves rowing boat "wiggle" problem
#4"to show that the balance of forces in this rig as the oars are pulled through the water" If the oars are pulled through the water, the boat wouldn't move.
What do you mean?
I suspect his point is that the blades of the oars, when immersed in the water, don't move (much) relative to the water. Approximating the blade as stationary in the water, we can see that the boat moves because of a lever effect. If the oars moved freely through the water there would be no thrust, as would be the case when rowing in liquid helium.
However, given the context, it seems a singularly pointless nitpick.
Re: Mathematician solves rowing boat "wiggle" problem
#5I wonder if some of those rigs are more fragile than the others. Perhaps some of them (rig (a) perhaps?) would wiggle more severely if the rowing forces were uneven while others would be fairly robust to differences in force.
Re: Mathematician solves rowing boat "wiggle" problem
#6There are several considerations that a rowing coach must make when deciding the rig of the boat as well as which rowers should occupy each seat.
These considerations may vary for each rower and include:
1. arc length (i.e. the distance traveled by the blade of the oar)
2. force curve (i.e. the amount of force applied during each part of the time the oar is in the water)
3. boat feel (it is a much different sensation rowing in the bow, middle and stern of the boat and different rowers are "better" in different parts of the boat)
Re: Mathematician solves rowing boat "wiggle" problem
#7> the serious problem of oscillating non-zero transverse moment in racing boats, otherwise known as wiggle.
Thank goodness for simplification of terminology.
Re: Mathematician solves rowing boat "wiggle" problem
#8Earlier quoted context omitted.
What do you mean?
I suspect his point is that the blades of the oars, when immersed in the water, don't move (much) relative to the water. Approximating the blade as stationary in the water, we can see that the boat moves because of a lever effect. If the oars moved freely through the water there would be no thrust, as would be the case when rowing in liquid helium. However, given the context, it seems a singularly pointless nitpick.
Especially considering that, in practice, oars move quite a lot through water. It’s fluid, after all; rowing is not like ski-poling yourself along.
Re: Mathematician solves rowing boat "wiggle" problem
#9"to show that the balance of forces in this rig as the oars are pulled through the water" If the oars are pulled through the water, the boat wouldn't move.
The oars move more than a little through the water. It isn't the immutability of the water that allows for traction, it is the drag, or perhaps resistance is a more appropriate term, that gives bite to the oars in the water.
Re: Mathematician solves rowing boat "wiggle" problem
#10I wonder if some of those rigs are more fragile than the others. Perhaps some of them (rig (a) perhaps?) would wiggle more severely if the rowing forces were uneven while others would be fairly robust to differences in force.
I wouldn't expect so, at least by the math. It looks is pretty simple. Number the seats 1 to 8, then for each side sum the seat numbers. The standard rig gives 16 and 20, but all 4 of these solutions are 18, 18.