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  #11  
Old November 12th 05, 11:37 PM
Doink
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Default Relativity question

Thanks! That clears it up....as far it can be cleared up....


Doink
"Paul Winalski" wrote in message
...
On Sat, 12 Nov 2005 12:00:33 -0800, "Doink"
wrote:

OK, Energy = Mass X Speed of Light Sq.

I understand the principle, that this translates to a BIG number and thus
a
lot of energy is contained in matter. Yes, matter is essentially frozen
energy. Stipulated.

By I'm thrown by the SPEED of light thing. If something has a mass of 10
grams and I multiply it by 386,000 mph it doesn't make sense. Is there a
scientific conversion from speed to some other unit????? How do you
multiply mass times speed? Or is it just representational? Can the
explanation be simplified?

Doink.

It all comes from the definition of energy.

Let's start with speed. The speed of an object is the distance it
travels in a unit amount of time. In standard MKS units, it's thus
measured in meters/sec (m/s). Speed is equal to distance traveled
divided by the time it took to cover the distance. Note we're
dividing meters by seconds and there's nothing strange or odd about
it.

Acceleration is the change in speed of an object per unit time. It's
thus measured in meters/second-squared (m/s**2).

The force required to produce a particular acceleration is
proportional to the mass of the object being accelerated. (F=ma).
Hence the MKS unit for force, the Newton, is one
kilogram*meter/second-squared (Kg*m/s**2).

Energy is a force applied over a distance. Hence the MKS unit for
energy, the Joule, is one Newton-meter, or one
kilogram*meter-squared/second-squared (Kg*m**2/s**2).

Power is energy expended per unit time. Hence the MKS unit for
power, the Watt, is one Joule/second (Kg*m**2/s**3). Utilities
sell electricity in energy units (power applied over time), which
is why it's sold in kilowatt-hours (one kilowatt-hour is 3600000
Joules).

So now go back to Einstein's formula: E=m*c**2. The MKS unit for E
is the Joule, for m is the kilogram, and for c is meters/second. So
you can see it all works out--we get Kg*m**2/s**2, the correct units
for a Joule.

-Paul W.
----------
Remove 'Z' to reply by email.



  #12  
Old November 13th 05, 11:27 AM
oriel36
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Posts: n/a
Default Relativity question


Sam Wormley wrote:
oriel36 wrote:
To Sam

The so-called 'genius' of reducing the astronomical effect due to
finite light speed to mathematical notation 'c' is just another way to
conceal the geometrical roots of the insight byOle Roemer.


For Gerald -- Measuring the Speed of Light
http://www.colorado.edu/physics/2000...es/jupiter.jpg
http://www.colorado.edu/physics/2000..._evidence.html


The Romerian jewel of this particular refinement of Copernican
heliocentricity is an observational effect.Using the rotation of the
foreground Milky Way stars and observed supernova representing external
parent galaxies,it is one of the most exciting avenues of astronomy
since Copernican/Keplerian heliocentricity.

You homocentric freaks won't even recognise how heliocentricity is
inferred through retrogrades and being incompetent have diluted the
Copernican insight to a worthless and self serving,
cretinous,relativistic end.

http://www.answers.com/topic/copernican-principle

You are too dumb to recognise that dropping the stellar background from
the motions of the planets and substituting the background with the
annual orbital motion of the Earth infers heliocentricity.You freaks of
humanity imagine that an observer on the Sun is required -

"For to the earth they appear sometimes direct, sometimes stationary,
nay, and sometimes retrograde. But from the sun they are always seen
direct..."

http://members.tripod.com/~gravitee/phaenomena.htm

If you can live with that Newtonian garbage you can live with anything
but don't even try to comprehend the Keplerian or Roemerian refinements
to true heliocentricity.

Go hug your telescopes but that is all you have but that never made a
person an astronomer.

  #13  
Old November 13th 05, 02:12 PM
Sam Wormley
external usenet poster
 
Posts: n/a
Default Relativity question

oriel36 wrote:
Sam Wormley wrote:

oriel36 wrote:

To Sam

The so-called 'genius' of reducing the astronomical effect due to
finite light speed to mathematical notation 'c' is just another way to
conceal the geometrical roots of the insight byOle Roemer.


For Gerald -- Measuring the Speed of Light
http://www.colorado.edu/physics/2000...es/jupiter.jpg
http://www.colorado.edu/physics/2000..._evidence.html



The Romerian jewel of this particular refinement of Copernican
heliocentricity is an observational effect.Using the rotation of the
foreground Milky Way stars and observed supernova representing external
parent galaxies,it is one of the most exciting avenues of astronomy
since Copernican/Keplerian heliocentricity.

You homocentric freaks won't even recognise how heliocentricity is
inferred through retrogrades and being incompetent have diluted the
Copernican insight to a worthless and self serving,
cretinous,relativistic end.


ILLUCID
  #14  
Old November 14th 05, 12:59 AM
Llanzlan Klazmon
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Posts: n/a
Default Relativity question

"Doink" wrote in
:

That's what I was looking for....A sort of scientific conversion unit.
For my purposes, I don't need to carry out the formula, just be able to
understand the relationship between what's expressed as speed figuring
into a formula involving mass. Your explanation was exactly what I was
looking for. Thank you!



You can use any units you like as long as you are consistant. The most
commonly used systems in science and engineering are either the cgs system
as used by Hilton or the mks system. Mixing units gets you into trouble as
NASA found out a while back when one of their Mars probes missed!!

Klazmon.




Doink
"Hilton Evans" wrote in message
ink.net...
"Doink" wrote in message
...
OK, Energy = Mass X Speed of Light Sq.

I understand the principle, that this translates to a BIG number and
thus a
lot of energy is contained in matter. Yes, matter is essentially
frozen energy. Stipulated.

By I'm thrown by the SPEED of light thing. If something has a mass of
10 grams and I multiply it by 386,000 mph it doesn't make sense.


First if your multiplying by just speed then you're using the
formula incorrectly.

Is there a
scientific conversion from speed to some other unit????? How do you
multiply mass times speed? Or is it just representational? Can the
explanation be simplified?



1 erg (cgs unit of energy) = 1 gram x cm^2/sec^2. Notice this has
the same units as kinetic energy i.e. mass x speed^2.
10 grams x c^2 = 10 x (2.997925x10^10 cm/sec)^2 = 9.0x10^21 ergs, or
9000 billion billion ergs. Don't try this conversion at home.

--

Hilton Evans
---------------------------------------------------------------
Lon -71° 04' 35.3"
Lat +42° 11' 06.7"
---------------------------------------------------------------
Webcam Astroimaging
http://home.earthlink.net/~hiltoneva...troimaging.htm
---------------------------------------------------------------
ChemPen Chemical Structure Software
http://www.chempensoftware.com





  #15  
Old November 14th 05, 01:19 AM
David G. Nagel
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Posts: n/a
Default Relativity question

Llanzlan Klazmon wrote:
"Doink" wrote in
:


That's what I was looking for....A sort of scientific conversion unit.
For my purposes, I don't need to carry out the formula, just be able to
understand the relationship between what's expressed as speed figuring
into a formula involving mass. Your explanation was exactly what I was
looking for. Thank you!




You can use any units you like as long as you are consistant. The most
commonly used systems in science and engineering are either the cgs system
as used by Hilton or the mks system. Mixing units gets you into trouble as
NASA found out a while back when one of their Mars probes missed!!

Klazmon.


The best unit of measurement that I have found is: Furlongs per
fortnight. It features a long base measurement that can be expanded to a
very long distance with out accumulating much error due to calibration
and a long time base which can also reduce error due to the long base
line. 8^)...

Posted April First.....




Doink
"Hilton Evans" wrote in message
hlink.net...

"Doink" wrote in message
news:VaidnRMEAvlO1OvenZ2dnUVZ_tKdnZ2d@trueband. net...

OK, Energy = Mass X Speed of Light Sq.

I understand the principle, that this translates to a BIG number and
thus a
lot of energy is contained in matter. Yes, matter is essentially
frozen energy. Stipulated.

By I'm thrown by the SPEED of light thing. If something has a mass of
10 grams and I multiply it by 386,000 mph it doesn't make sense.

First if your multiplying by just speed then you're using the
formula incorrectly.


Is there a
scientific conversion from speed to some other unit????? How do you
multiply mass times speed? Or is it just representational? Can the
explanation be simplified?


1 erg (cgs unit of energy) = 1 gram x cm^2/sec^2. Notice this has
the same units as kinetic energy i.e. mass x speed^2.
10 grams x c^2 = 10 x (2.997925x10^10 cm/sec)^2 = 9.0x10^21 ergs, or
9000 billion billion ergs. Don't try this conversion at home.

--

Hilton Evans
---------------------------------------------------------------
Lon -71° 04' 35.3"
Lat +42° 11' 06.7"
---------------------------------------------------------------
Webcam Astroimaging
http://home.earthlink.net/~hiltoneva...troimaging.htm
---------------------------------------------------------------
ChemPen Chemical Structure Software
http://www.chempensoftware.com





  #16  
Old November 14th 05, 01:56 AM
lal_truckee
external usenet poster
 
Posts: n/a
Default Relativity question

Llanzlan Klazmon wrote:

You can use any units you like as long as you are consistant. The most
commonly used systems in science and engineering are either the cgs system
as used by Hilton or the mks system.


I've always been amused by the mixed units - there is no "unitary"
system of units (which would be meters-grams-seconds: mgs) while there
is a 1/100 meters-grams-second (cgs) and a meters-1000 grams-seconds
(mks) system. Quelle bizarre.
  #17  
Old November 14th 05, 03:00 AM
Brian Tung
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Posts: n/a
Default Relativity question

Doink wrote:
By I'm thrown by the SPEED of light thing. If something has a mass of 10
grams and I multiply it by 386,000 mph it doesn't make sense. Is there a
scientific conversion from speed to some other unit????? How do you
multiply mass times speed? Or is it just representational? Can the
explanation be simplified?


The problem is that energy is a pretty abstract concept. You can't
point to some place on a brick and say, "There's its energy," the way
you can spread your hand against it and say, "That's its width," or
pick it up and say, "That's how much it weighs."

Nevertheless, if you drop a brick from shoulder height onto your foot,
it'll hurt a lot and may break some bones if it's heavy enough, whereas
the same brick if dropped from a height of an inch will merely make you
look foolish. The only real difference between the two situations is
the speed with which the brick hits your foot. In one case, the brick
strikes your foot with a gentle thud, and in the other, it has had some
time to build up speed and land on your foot with considerable impact.

Some enterprising soul may have decided to try to quantify this effect,
and rather than using his foot as the impact meter, decided to use some
other absorbing substance. We might use styrofoam, for instance. If
you drop a brick onto a block of styrofoam, it sinks partway in before
coming to a stop. That's because the styrofoam exerts an upward force
on the brick, and it take some time before enough force has been applied
to bring the brick to a complete stop.

If you stack two bricks, one on top of the other, before dropping them
onto the styrofoam, the pile will sink further in (assuming you drop
it from the same height as before), because the styrofoam exerts just
as much force as before, and that same force has to be applied for more
time to stop the greater brickage. For "ideal" styrofoam, we might
determine that the indentation is just twice as deep as before; for a
pile of three bricks (with therefore three times the brickage), it would
be three times as deep; and so on.

Alternatively, we could drop one brick as before, but from a greater
height, and see how much higher we have to go before we also get twice
as deep an indentation, or three times, or whatever. Again assuming
that we have ideal styrofoam, we find that we need only drop it from
twice as great a height, or three times, or whatever.

As a result of these observations, we might define a new quantity,
called *energy*, which is a measure of the impact with which the brick
hits the styrofoam. Since it's proportional to brickage for a given
height, and also proportional to height for a given brickage, we might
assume that it would be proportional to brickage times height, and we
would be right--except that we probably want a more dignified and
general term for "amount of stuff" in the brick than "brickage."
Following Newton, we use the term "mass." In that case, we can write

E = kmh

where E, m, and h stand for energy, mass, and height, respectively,
and k is the constant of proportionality. What would that be? With
hindsight, it is not so hard to see. If we were on the Moon, for
instance, dropping a brick is not as painful as it is on the Earth,
since the Moon's gravity is weaker. We might guess, then, that it is
the Earth's gravity, denoted g, that is the constant of proportionality,
which gives us

E = gmh

We emphasize that there is no obvious physical interpretation of this
product of three quantities. It's not as though you're measuring the
volume of the brick and therefore multiply the three dimensions. The
energy is just a quantity we defined to measure a property of interest.

Then again, we need not drop the brick. We can throw it from the side,
and as long as we attain whatever speed was derived from gravity when
we dropped it, we should get the same effect. To find out what that
effect is, we need to find out what speed a brick achieves when dropped
from a height of h. It turns out to be

v = sqrt(2gh)

where v is the square root function. In that case, we also have
v^2 = 2gh, (v^2)/2 = gh, and then

E = (mv^2)/2

which you might notice has the same units as mc^2 in Einstein's
equation. In the mks system, mass is measured in kilograms, and
velocity in meters per second. Thus, energy is measured in units of
kilogram-meters-squared-per-second-squared, an ungainly mouthful that
is given the special unit name of "joule." For instance, according
to this formula, a brick with a mass of 1 kilogram and a velocity of
4 meters per second (about 9 mph) is 8 joules, since half of 4
squared is 8.

You may have noticed that these formulas describe the energy of the
brick at two different moments in time. The first gives the energy
of the brick before it's been dropped, whereas the second gives the
energy just before it hits the styrofoam (or your foot). We can put
it another way: the first gives the energy due to the brick's position,
which we call its potential energy; and the second gives the energy
due to the brick's velocity, which we call its kinetic energy. It's
better therefore to write them as we often do, as

PE = mgh

KE = (1/2) mv^2

where I've slightly reformatted the equations according to tradition.

Incidentally, those equations can characterize the brick at different
points throughout its fall, not just at the start and at the end. At
the start, a brick's PE might be 16 joules, but since it's not moving,
its KE must be zero. Conversely, as it strikes the styrofoam, its KE
is 16 joules, but since its height is zero, its PE has to be zero, too.
It's tempting to think that throughout the fall, the KE plus the PE
must be 16 joules, and that thought turns out to be true: Although both
KE and PE are constantly changing, with KE increasing and PE decreasing,
they change in such a way that their *sum* is constant.

Another way of saying this is that the brick's total energy is
conserved. There's no reason why this *has* to be true--it's just our
common experience that it *is* true. You can raise the brick back to
its original height, thus restoring its PE--but then in order to do
that, you have to use up at least 16 joules worth of energy. In fact,
you have to exert more, the rest of it being wasted as heat.

There are lots of conservation laws, by the way: conservation of energy,
of linear momentum, of angular momentum, and so forth. Before Einstein
formulated his theory of relativity, there was also a law of the
conservation of mass. This seems pretty straightforward, since in
everyday experience, you can't just destroy mass; we merely shuffle it
from one place to another. We can burn wood, it is true, and in so
doing, it seems to vanish, but careful chemical experiments demonstrated
that what really happened was that the wood was oxidized and the loss of
mass in the wood we burned was really transformation into carbon dioxide
and other molecules that dispersed into the air. So it seemed that mass
really was conserved.

But then Einstein came along and demonstrated convincingly that mass was
just another form of energy--albeit extremely concentrated. This was
his famous formula E = mc^2. (Incidentally, that mass is relativistic
mass. Physicists generally prefer to deal with proper mass, also known
as rest mass, in which case the formula is the somewhat less pithy
E^2 = p^2c^2 + m^2c^4, where p is the object's momentum.) Note, though,
that this formula still gives energy in good old units of kilogram-
meters-squared-per-second-squared, or joules. It is therefore entirely
consistent with the definitions of PE and KE.

By Einstein's law, we can make mass vanish, but in doing so, we produce
an enormous amount of energy. In order to build up enough velocity to
create 16 joules upon impact, we must drop a 1-kilogram brick from a
height of about 1.6 meters (about 5 feet), assuming g = 10 meters per
second per second. That same brick, if converted entirely into energy
according to Einstein's formula, would yield an amazing 90 million
billion joules. This conversion is what allows the Sun, for instance,
to get such wholesale returns of energy from such a trifling investment
of hydrogen (to paraphrase Twain for a moment).

It works the other way around, too: We can create matter, provided we
throw in enough energy. There's a catch, though. Whenever we create a
particle, it seems we have to create its corresponding antiparticle.
We can create an electron if we put in about a million electron volts of
energy (electron volts are also units of energy, which are much smaller
than joules and therefore convenient when dealing with subatomic
particles), but we have to create the anti-electron, too, also known as
the positron. There doesn't seem to be any way around this, and--you
guessed it--this too has to do with conservation laws.

Finally, an electron volt is called that because it's the amount of
energy required to push an electron "the wrong way"--say, from a
battery's positive terminal to its negative terminal--across a potential
of one volt. In other words, to push an electron through a wire from
the nubby end of a AA battery to its flat end requires an investment of
1.5 eV. You can see why electron volts are so tiny.

Nevertheless, it's the same kind of energy, which is why you can create
energy by using gravity (usually falling water instead of falling
bricks), and using that energy to push electrons the wrong way--uphill,
so to speak. Then you let them go the natural way, and they can power
your appliances.

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt
  #18  
Old November 14th 05, 10:26 AM
Martin Brown
external usenet poster
 
Posts: n/a
Default Relativity question

Brian Tung wrote:

Doink wrote:

By I'm thrown by the SPEED of light thing. If something has a mass of 10
grams and I multiply it by 386,000 mph it doesn't make sense. Is there a
scientific conversion from speed to some other unit????? How do you
multiply mass times speed? Or is it just representational? Can the
explanation be simplified?


The problem is that energy is a pretty abstract concept. You can't
point to some place on a brick and say, "There's its energy," the way
you can spread your hand against it and say, "That's its width," or
pick it up and say, "That's how much it weighs."

Nevertheless, if you drop a brick from shoulder height onto your foot,
it'll hurt a lot and may break some bones if it's heavy enough, whereas
the same brick if dropped from a height of an inch will merely make you
look foolish. The only real difference between the two situations is
the speed with which the brick hits your foot. In one case, the brick
strikes your foot with a gentle thud, and in the other, it has had some
time to build up speed and land on your foot with considerable impact.


This is what I found so scary about the OPs question. It isn't really
about relativity at all but about basic classical kinetic energy.

You can measure velocity more or less directly by Doppler shift, but
without knowing the mass of the moving object there is no way to find
its energy.

Momentum delivered to the foot scales with velocity, but the energy
delivered and damage inflicted scales with velocity squared.

Some enterprising soul may have decided to try to quantify this effect,


One place where the effects of kinetic energy are felt in ordinary life
are the stopping distances for a car. The thinking time increases
linearly with speed, but the distance needed to make an emergency stop
by braking hard scales with the square of the initial speed.

It would go some way to explaining the prevalence of high speed
tailgating if many people have no idea how much further it will take
them to stop at high speeds.

Regards,
Martin Brown
  #19  
Old November 14th 05, 10:47 AM
Brian Tung
external usenet poster
 
Posts: n/a
Default Relativity question

Martin Brown wrote:
This is what I found so scary about the OPs question. It isn't really
about relativity at all but about basic classical kinetic energy.


Tell me about it. I set out to write a reasonably short (well, four
or five paragraphs, really) bit about why energy has the units it does,
and I just couldn't close the explanation without all that extra text.

(Really.)

--
Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt
  #20  
Old November 14th 05, 07:40 PM
oriel36
external usenet poster
 
Posts: n/a
Default Relativity question


Sam Wormley wrote:

oriel36 wrote:
Sam Wormley wrote:

oriel36 wrote:

To Sam

The so-called 'genius' of reducing the astronomical effect due to
finite light speed to mathematical notation 'c' is just another way to
conceal the geometrical roots of the insight byOle Roemer.


For Gerald -- Measuring the Speed of Light
http://www.colorado.edu/physics/2000...es/jupiter.jpg
http://www.colorado.edu/physics/2000..._evidence.html



The Romerian jewel of this particular refinement of Copernican
heliocentricity is an observational effect.Using the rotation of the
foreground Milky Way stars and observed supernova representing external
parent galaxies,it is one of the most exciting avenues of astronomy
since Copernican/Keplerian heliocentricity.

You homocentric freaks won't even recognise how heliocentricity is
inferred through retrogrades and being incompetent have diluted the
Copernican insight to a worthless and self serving,
cretinous,relativistic end.


ILLUCID


O.K.

http://www.strangepersons.com/images/content/7404.jpg

See that picture of Jupiter's moon Io,well there is an observational
effect in that image directly related to Ole Romer's original
discovery.

The original discovery was known as the Equation of Light or Mora
Luminis and refers to the positional adjustment due to the finite
distance light travels.

As the resolution is entirely geometrical and based on the variations
in the heliocentric motions between Jupiter and Earth,the anomalous
slowing down and speeding up of Io's motion as it orbited Jupiter was
accounted for as an observation an effect,its motion neither actual nor
an illusion.Looking at the image above of Io and its shadow,it true
position as viewed from an orbitally moving Earth can only be
considered from the point of view of a mean motion.Just like the
Equation of Time equalises the variations in the natural unequal day to
the equable 24 hour day then so does the Equation of Light equalise the
anomalous motions hence the astronomical use of the word 'equation'
which has nothing in common with its non geometric counterpart.

So,let's take Newton apart -

" Some inequalities of time may arise from the Excentricities of
the Orbs of the Satellites; [etc.]... But this inequality has no
respect to the position of the Earth, and in the three interior
Satellites is insensible, as I find by computation from the Theory of
their Gravity. " Opticks 1704

The inequality of times sure does from the motion and position of the
Earth , Io happens to be Jupiter's innermost satellite and Roemer's
insight has nothing to do with gravity.

It is easier to comprehend Roemer's insight without having to go
through the bluffing and blustering of Newton and I assume there are
people who would not mind accepting the real challenge that Roemer's
insight provides.

The uncharted territory of modelling the positions of galaxies to the
rotation of the foreground Milky Way stars using supernova data and
Roemer's insight is breathtaking but the outlines of these mountainous
regions for real human endeavor is still laid low by the manipulations
of a 17th century theorist who had no feel for these things.

All this rubbish of source dependence or homocentric observer depedence
is really uneccessary for no such perceptions are astronomically
demanded no more than the speed of sound and the passage of a jet
plane requires that you jump from a plane view to an earth based view
and grapple with what the person hears.It is not even that interesting
and in matters of finite light speed,it is entirely useless.

This era is more crucial than any else for a silence has descended
borne of Newtonian/relativistic novelistic exhaustion,whether a number
of people resolve to take a conceptual audit going right back to the
transfer of pre-Copernican astronomy to Copernican heliocentricity,the
golden opportunity to restore a much needed balance will be lost.

It may be that Western empirical cancer will kill the astronomical
discipline entirely and another civilisation will pick it up as
happened before for no civilisation can live with this insincerity that
hijacks genuine accomplishments and spins a myth from misconduct and
intellectual fraud.That is what Newtonian ballistics applied to
planetary motion amounts to.

 




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