Rotation - Over Rotation vs Just Enough

[terry]

I've removed Lawrence's messages from this thread.
The one thing I cannot countenance here is gratuitous rudeness and insults.

Lawrence, it takes a lot to move me to end someone's posting privileges but you're thisclose.

[CoachKris]

Originally Posted by aquarius

So, your hand is a bullet. What you're saying (and others with you) is that simply rotating the barrel of your gun along the cylinder's axis will send the bullet to its target. All I can say is: good luck!

not exactly, lets say that it all starts with a kick - spark from a primer ->then your hips are turning adding more energy in - powder explosion -> next bullet travels through rifled barrel - your shoulders that are adding more rotation and it all fires as your arm spears into water

thats more likely the way i see it ;)

[FrankJ]

Originally Posted by CoachKris

Without gravity force there would be nothing that could stop you from doing so :)

No, this is wrong. In the absence of gravity, swinging your arms would bring you nowhere, unless you apply force on an external body. This is basic physics, you are free to not believe it in, but that does not change the fact that spearing you arm forward when you swim, does not give you propulsion.

[FrankJ]

Originally Posted by CoachKris

not exactly, lets say that it all starts with a kick - spark from a primer ->then your hips are turning adding more energy in - powder explosion -> next bullet travels through rifled barrel - your shoulders that are adding more rotation and it all fires as your arm spears into water

thats more likely the way i see it ;)

You may see it like this,or you may feel it like this, but this is not the way it is.

Try spearing forward without pulling your opposite arm underwater.

And also, try rotating without pulling with you arm. In both cases you will go nowhere (save from some displacement of water backwards, assuming it is even there at all)

[CoachKris]

fjconti72 'water' is that external body that you apply force on and anchored second arm is your point of force application

again please explain a bit further what basics physics are you on about please be a bit more specific

[JBeaty]

Originally Posted by fjconti72

You may see it like this,or you may feel it like this, but this is not the way it is.

Try spearing forward without pulling your opposite arm underwater.

And also, try rotating without pulling with you arm. In both cases you will go nowhere (save from some displacement of water backwards, assuming it is even there at all)

Fjconti, on a number of occassions, CoachDave has demonstrated both rotating and spearing forward by using only the recovering arm. He keeps his anchored arm at his side in the skating position.

The keys are good balance, finding the right amount of rotation and spearing forward to the right depth.

You won't go very far or very fast but the recovering arm can rotate you and move you forward without the use of the other arm.

[FrankJ]

Originally Posted by CoachKris

fjconti72 'water' is that external body that you apply force on and anchored second arm is your point of force application

again please explain a bit further what basics physics are you on about please be a bit more specific

And in fact as I said, the force applied by the arm underwater is what provides propulsion. Not shooting the leading arm forward as you implied. The basic physics I'm referring to are Newton's laws of motion, you can look them up yourself. But you cannot move around in space or water zero G by swinging your arms.

[FrankJ]

Originally Posted by JBeaty

Fjconti, on a number of occassions, CoachDave has demonstrated both rotating and spearing forward by using only the recovering arm. He keeps his anchored arm at his side in the skating position.

The keys are good balance, finding the right amount of rotation and spearing forward to the right depth.

You won't go very far or very fast but the recovering arm can rotate you and move you forward without the use of the other arm.

Do you refer to one arm freestyle? If so, one arm will be pushing water.

If not, do you imply that he can move forward across the pool just by rotation and spearing? If so, again as I suggest above, asymmetrical water displacement by body and arm movement might cause that, but I doubt it is very significant. Further, it does NOT imply that rotation along an axis collinear with the direction of movement will contribute to forward motion.

[JBeaty]

Originally Posted by fjconti72

Do you refer to one arm freestyle? If so, one arm will be pushing water.

If not, do you imply that he can move forward across the pool just by rotation and spearing? If so, again as I suggest above, asymmetrical water displacement by body and arm movement might cause that, but I doubt it is very significant. Further, it does NOT imply that rotation along an axis collinear with the direction of movement will contribute to forward motion.

He doesn't pull with the spearing arm. He doesn't pull with the other arm, as I stated, it is at his side.

I have watched Dave do this demonstration a number of times. If he didn't rotate as he speared, he would not move forward. Without the rotation, he wouldn't be able to send his spearing arm in the direction and depth that it needs to travel to move forward.

This demonstration shows how the spearing arm and rotation work together to aid in forward travel. It is not one arm freestyle where the spearing arm becomes the pulling arm.

Once the rotation and spear are complete, the person travels forward until gravity causes the person to start to sink.

[FrankJ]

Originally Posted by JBeaty

He doesn't pull with the spearing arm. He doesn't pull with the other arm, as I stated, it is at his side.

I have watched Dave do this demonstration a number of times. If he didn't rotate as he speared, he would not move forward. Without the rotation, he wouldn't be able to send his spearing arm in the direction and depth that it needs to travel to move forward.

This demonstration shows how the spearing arm and rotation work together to aid in forward travel. It is not one arm freestyle where the spearing arm becomes the pulling arm.

Once the rotation and spear are complete, the person travels forward until gravity causes the person to start to sink.

I would like to watch a video. But if this is correct, then moving the body and the arm must displace water asymmetrically, as discussed many times, above and in the 'important new insight...' thread. Certainly it does not imply that rotation directly contributes to forward motion as it does in baseball, or that swinging arms generates motion per se.