dumb swimming question

"Chris" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

If you want to swim fast how should your fingers be in the water as you
pull? open/spread to increase surface area or together? I'm talking

about

Quoted message said:

regular freestyle or whatever it's called.

a) Freestyle is a type of race, which is usually swum front crawl; although
any method or locomotion is allowed, excepting such things as pulling of the
side or lane markers, pushing off the bottom, etcetera.

b) The fingers together/apart issue was a hoary one in swimming until
Schleihauf's work about 30 years ago. It is now known that fingers together
allow the hand to generate more (much) lift. Although this component is not
the only one contributing to swimming propulsion, separating the fingers has
a negligeable effect on the others.

c) the belief that seperating the fingers will "increase the surface area"
indicates that the person advancing this is lacking basic geometrical
understanding.

Keep your fingers together; and your hand flat and stiff.

jtaylor said:

c) the belief that seperating the fingers will "increase the surface area"
indicates that the person advancing this is lacking basic geometrical
understanding.

Keep your fingers together; and your hand flat and stiff.

Actually, the belief that separating your fingers will increase surface
area is very reasonable if you understand the properties of water. That
is why a straight forward conclusion could not be drawn until you do
some tests. If you understand that water has the unique feature of
having surface tension, the theory will make sense. this means that
water molecules tend to stick together until there is sufficient force
to break them appart. This is a unique property of water, but not of
other liquids. If you think about it, when you push water with your
closed hand, the water molecules that are on the edges of the palm will
bind to some other water molecules, pushing back more water than the
water that is directly behind the hand. If you keep your fingers
appart, the theory would indicate that the water molecules behind each
finger would be attached to water molecules next to them, therefore,
pushing back more water with fingers opened than with fingers closed.
So, the theory is sound. However, theory does not always = practice,
because in reality, there are other forces that may be involved. Hence,
the need for experimenting. However, people who assume that keeping
fingers spread would get more propulsion are making a very good
hypothesis.

I have tried swimming with both fingers opened and closed. I can't
really tell much of a difference. When I spread my fingers, I feel that
I am grabbing more water. Yet, I don't decrease my stroke count, which
indicates to me, that there are many other factors that lead to
propulsion, as you suggest. If I focus on closing my fingers tight
together, it feels weird and uncomfortable. So, I swim with my hands
relaxed, but mostly closed.

Andres

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

jtaylor said:

c) the belief that seperating the fingers will "increase the surface

area"

Quoted message said:

Quoted message said:

indicates that the person advancing this is lacking basic geometrical
understanding.

Keep your fingers together; and your hand flat and stiff.

Actually, the belief that separating your fingers will increase surface
area is very reasonable if you understand the properties of water. That
is why a straight forward conclusion could not be drawn until you do
some tests. If you understand that water has the unique feature of
having surface tension,

Surface tension does not exist below the surface.

Quoted message said:

the theory will make sense. this means that
water molecules tend to stick together until there is sufficient force
to break them appart. This is a unique property of water, but not of
other liquids.

This is completely and utterly wrong.

<[email hidden]> wrote about surface tension:

Quoted message said:

This is a unique property of water, but not of
other liquids.

Just a slight correction: All liquids have surface tension. Water's is
just very noticeable compared to most others because of its unique molecular
shape.

"Drew Compston" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

<[email hidden]> wrote about surface tension:

Quoted message said:

This is a unique property of water, but not of
other liquids.

Just a slight correction: All liquids have surface tension. Water's is
just very noticeable compared to most others because of its unique

molecular

Quoted message said:

shape.

Typical values for surface tension of water range from about 60 (dynes/cm,
at boiling, 1atm) up to somewhere near 75 near freezing (also 1atm). Values
for other common liquids can be either higher or lower - mercury, for
example is over 450 at similar temperatures; glycerol is around 65; ethanol
is a bit above 20; and blood is almost 40.

While it is technically true that water has a unique molecular structure, so
do all other molecules. The polar nature of the water molecule, which is
responsible for the cohesive bonding, is also present in countless other
molecules; but is not a requisite for that degree of surface tension -
diethyl ether, for instance, has a dielectric constant of 4.34 (water is
80), yet its surface tension is over 70.

"Drew Compston" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

<[email hidden]> wrote about surface tension:

Quoted message said:

This is a unique property of water, but not of
other liquids.

Just a slight correction: All liquids have surface tension. Water's is
just very noticeable compared to most others because of its unique

molecular

Quoted message said:

shape.

Typical values for surface tension of water range from about 60 (dynes/cm,
at boiling, 1atm) up to somewhere near 75 near freezing (also 1atm). Values
for other common liquids can be either higher or lower - mercury, for
example is over 450 at similar temperatures; glycerol is around 65; ethanol
is a bit above 20; and blood is almost 40.

While it is technically true that water has a unique molecular structure, so
do all other molecules. The polar nature of the water molecule, which is
responsible for the cohesive bonding, is also present in countless other
molecules; but is not a requisite for that degree of surface tension -
diethyl ether, for instance, has a dielectric constant of 4.34 (water is
80), yet its surface tension is over 70.

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

In article <[email hidden]>,

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

I think they're talking about friction.

In article <[email hidden]>,

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

I think they're talking about friction.

<[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

If you will read up the thread a bit you'll find this has already been
pointed out.

"Jeffrey T. Spaulding" <[email hidden]> wrote in
message news:[email hidden]...

Quoted message said:

In article <[email hidden]>,

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

I think they're talking about friction.

This indicates either a total lack of knowledge of the principles involved,
or an eagerness to misunderstand that would be pitiful from any normal
source.

(No points for pointing out that a short form of the latter is a four-letter
word starting with "t" and ending with "l".)

"Jeffrey T. Spaulding" <[email hidden]> wrote in
message news:[email hidden]...

Quoted message said:

In article <[email hidden]>,

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

I think they're talking about friction.

This indicates either a total lack of knowledge of the principles involved,
or an eagerness to misunderstand that would be pitiful from any normal
source.

(No points for pointing out that a short form of the latter is a four-letter
word starting with "t" and ending with "l".)

<[email hidden]> wrote

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

Technically, you are right. However, surface tension and viscosity are
related because they are both caused by intermolecular forces. So, while it
may not be completely accurate to think of the concept in terms of surface
tension, as long as it gets the point across I think it does not matter what
you call it.

"jtaylor" <[email hidden]> wrote

Quoted message said:

While it is technically true that water has a unique molecular structure,
so
do all other molecules. The polar nature of the water molecule, which is
responsible for the cohesive bonding, is also present in countless other
molecules; but is not a requisite for that degree of surface tension -
diethyl ether, for instance, has a dielectric constant of 4.34 (water is
80), yet its surface tension is over 70.

You are right. There are a number of reasons that a liquid can have a high
surface tension. Water has a high surface tension because of the large
intermolecular forces caused by its polar shape. Other liquids may have
other reasons.

<[email hidden]> wrote

Quoted message said:

I think you are confusing "surface tension" and "viscosity". Surface
tension is a measurement of the cohesive energy present at an interface
between two fluids, which can be reinterpretated as a force per unit of
length at the interface. In the problem at hand there is no interface.

Technically, you are right. However, surface tension and viscosity are
related because they are both caused by intermolecular forces. So, while it
may not be completely accurate to think of the concept in terms of surface
tension, as long as it gets the point across I think it does not matter what
you call it.

"jtaylor" <[email hidden]> wrote

Quoted message said:

While it is technically true that water has a unique molecular structure,
so
do all other molecules. The polar nature of the water molecule, which is
responsible for the cohesive bonding, is also present in countless other
molecules; but is not a requisite for that degree of surface tension -
diethyl ether, for instance, has a dielectric constant of 4.34 (water is
80), yet its surface tension is over 70.

You are right. There are a number of reasons that a liquid can have a high
surface tension. Water has a high surface tension because of the large
intermolecular forces caused by its polar shape. Other liquids may have
other reasons.

Drew Compston said:

<[email hidden]> wrote

Quoted message said:

"jtaylor" <[email hidden]> wrote

This thread ruined last night's dinner.
Me to DH: Do you think I should keep my fingers closed?
Mumbled answer with full mouth.
Me: Considering surface tension and viscosity and all that.
Me (ten minutes later): okay, I won't call it tension. Surface energy.
Fingers closed?
Me: Yeah, they mentioned the molecular stuff. But do you think this
California chardonnay is pretty good for a screw-top?
Twenty minutes later: What is this, Fingers Open or Closed 401? Just the
bottom line and I'll get the salad.
Me: Look, just cut to the chase. No blue books here. No black holes.
Just fingers.

I gave up and ran out while the lecture continued. But I'm going to
continue to keep my fingers very slightly open because that's where they
want to go and my body has always made better choices than my mind.

Ruth Kazez

rtk said:

Drew Compston said:

<[email hidden]> wrote

Quoted message said:

"jtaylor" <[email hidden]> wrote

This thread ruined last night's dinner.
Me to DH: Do you think I should keep my fingers closed?
Mumbled answer with full mouth.
Me: Considering surface tension and viscosity and all that.
Me (ten minutes later): okay, I won't call it tension. Surface energy.
Fingers closed?
Me: Yeah, they mentioned the molecular stuff. But do you think this
California chardonnay is pretty good for a screw-top?
Twenty minutes later: What is this, Fingers Open or Closed 401? Just the
bottom line and I'll get the salad.
Me: Look, just cut to the chase. No blue books here. No black holes.
Just fingers.

I gave up and ran out while the lecture continued. But I'm going to
continue to keep my fingers very slightly open because that's where they
want to go and my body has always made better choices than my mind.

Ruth Kazez

Ruth,
Hilarious post, but you should have videotaped it for the group, since
it sounds like something that some would ponder for their remaining
years, and other would have something else to contemplate while swimming.
Madelaine

rtk said:

Drew Compston said:

<[email hidden]> wrote

Quoted message said:

"jtaylor" <[email hidden]> wrote

This thread ruined last night's dinner.
Me to DH: Do you think I should keep my fingers closed?
Mumbled answer with full mouth.
Me: Considering surface tension and viscosity and all that.
Me (ten minutes later): okay, I won't call it tension. Surface energy.
Fingers closed?
Me: Yeah, they mentioned the molecular stuff. But do you think this
California chardonnay is pretty good for a screw-top?
Twenty minutes later: What is this, Fingers Open or Closed 401? Just the
bottom line and I'll get the salad.
Me: Look, just cut to the chase. No blue books here. No black holes.
Just fingers.

I gave up and ran out while the lecture continued. But I'm going to
continue to keep my fingers very slightly open because that's where they
want to go and my body has always made better choices than my mind.

I think that will give the highest abount of friction and turbulence.
I don't know if that has much effect, if any, but the AFL will applaud
(American Friction League).

Sort of related....

hand flat or slightly cupped?

"David Hallsworth" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Sort of related....

hand flat or slightly cupped?

Flat.