Amaguriken

[bissek]

Your punches create vaccuum theory would only protect on consecutive punches. Your arms woud get scorched on the first one.
I just reworked the math. .6 meters of extension to a strike, wiht one arm striking while the other chamber gives 10ms/attack.
Also allowing impact to handle deceleration.
.6= .5*a*.01^2
a = 1200 m/s/s = 122g
v = 1200*.01 = 12 m/s
Doubling the number of punches takes you to a = 48000m/s/s = 4898g, v=240m/s, still subsonic.
My point about g-forces in the joints still holds. Ranma would be pissed if a cool martial arts technique had the long term affect of making it impossible to practice the art when he gets older.

[Neko-]

The joints would run into trouble sure... But prior to that you'd also have to deal with bloodpressure problems in the attacking arm.
Ever swing your arm around at high-speed (I tend to notice it if I turn around fast, and swing my arm out as a counter balance while doing it (looking almost like a backhand strike)) and notice the increase in bloodpressure in your hand?
If the arm actually did move that fast, the blood would most likely be pressurized enough to burst a vain. More speed = more pressure... Too much pressure = bursting hand.

[Daniel Jess Gibson]

Ranma does not necessarily have to ever stop moving he could use the bounce back from hitting the opponent/target to chamber his fist. Also Ranma doesn't have to decelerate because his arm can only go so far before it naturally bounces back (kind of like a rubber band) or gets pulled out of the socket.

The "bounce" is wasted energy (from Ranma's point of view) as it's energy that isn't going into damaging his opponent. Ranma would prefer it his fist stopped dead upon impact and he had to pull it back for the next strike.

Actually the bounce means more impact energy not less, because the object impacted takes both the initial inpact and the enrgy forcing the fist back.
I also believe he's only moving his fist a few inches after the original impact, a full retract is a waste of time and energy.

[antimatterenergy]

Your punches create vaccuum theory would only protect on consecutive punches. Your arms woud get scorched on the first one.

I don't really think the heat would overly bother Ranma because it would only exist until the vacuum is created. I can put my hand into a candle flame for more than a second so I doubt that the heat would overly bother Ranma becuase of the short time that he has to feel it and he has demonstrated that he can withstand extreme temperatures (Saffron heated up so hot that rock was melting and Ranma was not that far away from Saffron and this was before Ranma figured out how to turn on the ice staff. Ranma himself had also heated up to temperatures hot enough to set things on fire when Happosai gave Ranma a cold. It has also been demonstrated that Ranma's battle aura gives off heat generally not enough to burn stuff but since things require both a high enough heat and time exposed to the heat this isn't surprising. Paper for instance doesn't even burn until it reaches 451 degrees Fahrenheit (233 degrees Celsius) dependant on the type of paper and duration of exposure to the heat. )
As for it causing perment damage in Ranma considering that both cologne and happosai can do those speeds it's not that likely.

[bissek]

I already pointed out that Cologne knowing the technique and still having the use of her arms pretty much proves that the technique HAS to involve strengthening joints to survive the absurd g forces involved.
The real power Ryoga gained from the Breaking Point wasn't the ability to blow up inanimate objects with a touch, but the ability to stand within two feet of an exploding inanimate object and not get hurt. Basically, it increased the toughness of his body's tissue.
Perhaps the true strength of the Amaguriken isn't the ability to move parts of your body at speeds nearing mach 1, but the ability to withstand being accelerated to near mach 1 in 1/200th of a second. Basically, it toughens the bones. Neko's comment implies that it also strengthens the vein's ability to handle pressure.
What would be possible effects of this? First, if your arm can withstand five thousand gs, then the discomfort caused by any kind of armlock is negligible. The skeleton's ability to withstand massive amounts of force delivered at incredible speeds would make it a lot harder to break bones (Perhaps this is why Ranma survived all those mallets to the head?). The toughness granted to the circulatory system means that he'd be less vulnerable to some forms of heart disease. Plus, being able to withstand massive changes in pressure, both to the veins and the skeleton, means that Ranma is effectively immune to the bends (An incredibly painful and sometimes lethal condition caused by overly rapid depressurization in divers). Perhaps he can go into the underwater salvage business? Not needing decompression stops means that he can spend a lot more time underwater than any other diver would.

[nuclear death frog]

(Perhaps this is why Ranma survived all those mallets to the head?)

The mallet is an EXTREMELY. COMMON. SIGHT. GAG. WHICH. NEARLY. EVERYONE. USES.
*NOTHING* more.
It is, in fact, a gag that appears in many anime/manga series.
And seeing it treated as anything more than a sight gag is an incredible annoyance.

[Zwzn]

(Perhaps this is why Ranma survived all those mallets to the head?)

The mallet is an EXTREMELY. COMMON. SIGHT. GAG. WHICH. NEARLY. EVERYONE. USES.
*NOTHING* more.
It is, in fact, a gag that appears in many anime/manga series.
And seeing it treated as anything more than a sight gag is an incredible annoyance.

The mallet is an actual weapon in Ranma.5. Duck boy breaks one when Ranma trys to use it on him to get Duck boy to stop dating the sculpture. It is also canon that Akane's mallet blow K.O. Ranma out in the valintine's day arc.

[lwf58]

I'd better nip this one off before it grows. The debates about the fanon aspects of mallets in R.5 are endless and rarely get anywhere... a classic example of the old Heinlein quote, "you can lead a child to knowledge, but you cannot make him think."
This topic is about the canon, fanon, and r/l physical aspects of the kachuu tenshin amaguriken, not mallets. Since both major viewpoints about the mallet issue have been expressed, there will be no further posts about them permitted in this thread. If you really want to have an endless, fruitless argument about Ranma and mallets, create a new topic for it.

[Knight of L-sama]

1.2 meters he meant counting both the forward and backward motion (60cm (.6m or 2 feet) one way) is unnecessary and adds extra strain to the joint and muscles. It would be much more practical to only pull the arm back around a foot. This puts a lot less strain on the body and it takes a lot less energy to pull back when you don't fully extend.

I wasn't trying to do anything definitive, just trying to put a contraint limit on it. That 1.2m is pretty much the maximum distance his arm is going to have to travel.

[Ninsaneja]

And this is only because I viewed confusion or at least differing definitions of a "sonic boom."
A sonic boom is caused by the bunching of sound waves together as the thing creating them is traveling almost as fast or exactly as fast as sound travels. The sound waves magnify as they are much closer together and the object arrives at approximately the same time as the boom. It appears to be an explosion because the roaring of the engines of something going so fast is intensified and shortened.
Sonic booms do not occur for things traveling much faster than the speed of sound - you merely hear them "in reverse" so to speak, as the object will actually pass the sounds it is making - so you hear the more recent sound before the less recent sounds.
Hang on a moment, checking Wikipedia, the entirety above this point is from memory.
Ok, wikipedia states that past mach one it is termed a "supersonic shock cone" but otherwise I think I got it.
Ranma's fist would make a sonic boom only when moving nearly as fast as the speed of sound up to moving slightly faster. Afterwards it makes a normal sound. However! A sonic boom would not occur unless he was moving it in only one direction, as they are caused by a building up of sonic waves at the front or around there of the object, not merely by fast speeds.
So, definite answer, not only is "hundreds" clearly within the speed limit, a sonic boom is not created by a back and forth motion nor is it created at speeds faster than sound - So even if bizarrely the sound waves travelled back and forth with his hand it would not boom because his hand could be moving faster instead of exactly at the speed of sound.

[Neko-]

Plus, being able to withstand massive changes in pressure, both to the veins and the skeleton, means that Ranma is effectively immune to the bends (An incredibly painful and sometimes lethal condition caused by overly rapid depressurization in divers).

Correct me if I'm wrong, but the bends involve the expulsion of gasses from the blood-stream as a result of depresurisation.
And I quote from http://en.wikipedia.org/wiki/Decompression_sickness :

When the body is exposed to decreased pressures, such as when flying an un-pressurised aircraft to altitude, or during a scuba ascent through water, the nitrogen dissolved in the body comes out of solution. If nitrogen is forced to come out of solution too quickly, bubbles form in parts of the body, causing signs and symptoms ranging from itching and rashes, to joint pain, which is known as "the bends," to sensory failure, paralysis and death.

Even if the Amaguriken would provide toughness to the veins preventing rupture under extreme conditions, it will not protect Ranma from the bends since the training doesn't provide protection against this happening.

[Pale Wolf]

A sonic boom is caused by the bunching of sound waves together as the thing creating them is traveling almost as fast or exactly as fast as sound travels.

Nope. The boom is caused by breaking through those waves. Not by transonic speeds, by supersonic - direct quote from the wiki article that you claim to have referenced:
'A sonic boom is the audible component of a shock wave in air. The term is commonly used to refer to the air shocks caused by the supersonic flight of military aircraft or passenger transports such as Concorde (Mach 2.03, no longer flying) and the Space Shuttle (up to Mach 27 - Note, this high number is largely due to the high altitudes, therefore low air pressures, that the space shuttle flies at).'
However, there's actually proof that Ranma never gets even transonic (near the speed of sound) - no Prandtl-Glauert singularity forms (a condensation cloud around the moving object).

[antimatterenergy]

That a Prandtl-Glauert singularity doesn't form is not proof of Ranma's speed. It would not be created in the way that by Ranma's punches no matter the speed. One reason being that if Ranma is pushing away enough air to create a vacuum the cloud can't form becuase it can't form in a vacuum and if he's only lowering the air pressure it requires much greater speeds for the cloud to form. Second reason is that it only forms at around the speed of sound going slower it won't form or going faster and it won't form (depending on air pressure(low needs higher speeds), humidity (high and it can be done at lower speeds), etc...). Third reason being is that Ranma's arm is pistioning in a back and forth motion and not steadily going one way like airplanes that travel at super sonic speeds. Fourth and final reason I'm going to list is that Ranma is only going at those types of speeds for a few seconds at most cloud would need more time to form.

[Pale Wolf]

One reason being that if Ranma is pushing away enough air to create a vacuum the cloud can't form becuase it can't form in a vacuum and if he's only lowering the air pressure it requires much greater speeds for the cloud to form.

And neither of these is proven to be happening - you can't say 'because it doesn't work in my pet theory, it obviously isn't happening'.
By the way, a plane doesn't push the air away when it's going at that speed, it pushes through it - that's what going supersonic is all about. (Technically, if he were pushing the air away, he still wouldn't be going supersonic, because he'd be speeding up the sound)

going faster and it won't form

Wrong!
When you're going subsonic, it will never form. But when you're going supersonic, you must, at some point, go transonic - at that point, the singularity would form. It does not, therefore Ranma never reaches transonic speeds. And without reaching the lower velocity, he cannot reach supersonic speeds.

Third reason being is that Ranma's arm is pistioning in a back and forth motion and not steadily going one way like airplanes that travel at super sonic speeds.

It's going steadily for the length of one punch, repeatedly.

Fourth and final reason I'm going to list is that Ranma is only going at those types of speeds for a few seconds at most cloud would need more time to form.

Um... AM, the cloud forms fast enough to be around the midpoint of a transonic aircraft. Ie. instantly, for all intents and purposes.
And he doesn't need to be going at transonic speeds for great lengths of time - just long enough to cause the drop in air pressure and thus temperature that forms the singularity. The cloud will form regardless of the speed, as long as the pressure drop is created (In fact your argument that he's reducing the pressure increases the probability of a cloud's formation)
By the way:

A sonic boom would not occur unless he was moving it in only one direction, as they are caused by a building up of sonic waves at the front or around there of the object, not merely by fast speeds.

Wrong. It's caused by breaking through the shock waves. The moment you go supersonic, by definition, you are breaking those shock waves - those shock waves are the sound barrier.
The shock waves are simply formed by the pressure of an object moving through air, and as the speed is increased, they get bunched up into a single wave at the speed of sound. They do not need to build up, they form instantly. The boom is merely the effect of breaking through them.

[antimatterenergy]

I just looked at a few different websites wikipedia, http://www.fluidmech.net/tutorials/soni ... clouds.htm , and http://www.galleryoffluidmechanics.com/ ... g_sing.htm.
One of the things I noticed is that the cloud doesn't always form. It also mentions how the cloud forms under higher air pressure and higher humidity and only on steady level flight.
From third website:

Condensation caused by the Prandtl-Glauert singularity can be seen in steady level flight usually at low altitude under humid conditions.

From wikipedia artical on transonic:

At transonic speeds intense low-pressure areas form at various points around an aircraft. If conditions are right (i.e. high humidity) visible clouds will form in these low-pressure areas as shown in the illustration. These clouds remain with the aircraft as it travels. It is not necessary for the aircraft to reach supersonic speeds for these clouds to form.

As for not being able to create the cloud at subsonic speeds I'd like to quote the second site I listed

An aircraft can generate a Prandtl-Glauert condensation cloud without ever exceeding the speed of sound.

About a plane pushing through the air that is true but it is very untrue for Ranma. Ranma's body is mostly not moving with his arm continously moving back and forth occupying the same area of space repeatedly and therefore pushing the air out of that area instead of going through new air like a plane does.