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What is a Watt???
#61
Hi All,
The final 2nd version of the pdf is now attached to post 53 of this thread.
Enjoy!!!!

Happy New Year to one and all.

I have started a discussion thread for the pdf, it can be found HERE.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#62
Just posted the following on fb, I thought I should post it here too.

Apologies to all, but this damned matter keeps on coming up, time and again. THE reason is to "justify" GH "theory" and AGW, but to explain that is another post. For now, I just want to clear up, once and for all, that a watt can not be timeless, and niether can power figures ever be timeless. Both are tennents that much pseudo-science is based upon.

http://en.wikipedia.org/wiki/Power_%28physics%29
In physics, power is the rate at which energy is transferred, used, or transformed. The unit of power is the joule per second (J/s), known as the watt

ie power is amount over time.
Therefore a watt can not be timeless. If it is, then it is not a watt, it is a joule.

A joule is an amount of energy. It is merely that.
http://en.wikipedia.org/wiki/Joule

A Watt, which is a power figure, is exactly the same amount of energy as a joule over a time period, which is by default one second.
http://en.wikipedia.org/wiki/Watt

Put another way, a watt without time is a joule. There is no such thing as a timeless watt, THAT is why we have a joule....

The following might help people to understand, and by which to remember, the difference between a joule and a watt.

Power is amount over time.

A long time ago it was decided that in recognition of James Prescott Joule and his great works, that an amount of energy should be called a joule. A joule is the amount of energy expended (or work done) in applying a force of one newton through a distance of one metre (1 newton metre or N·m) for one second, or in passing an electric current of one ampere through a resistance of one ohm for one second. It was also decided that we will call the exact same amount of energy as a rate per time unit (by default a second) a Watt in recognition of James Watt's great works.

In short, a joule is an amount of energy, to which time can be added. A Watt is a rate, flow, or power, of the exact same amount of energy, which by default is over the time period of a second, unless otherwise specified. A Watt with no time component is simply an amount (which is a joule), it is not a power figure. Therefore using the term Watt, because it is a power figure, dictates that it is an amount over the time period of a second, (unless the time period is otherwise specified). A watt (which is a power figure) can not be timeless, period.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#63
Hi Derek. Note a lack of response here and wonder if it is too much info you are putting out.

I have my own simplistic view of the relationship between watts and joules as applied to black bodies. But when applied to a gas, I dunno. I have to accept the methods used by others until I hear of something better. I understand where you are going but I'm unable to offer any useful advice.

Clive Best made a post Why CO2 is not the cause of “Hothouse Venus” where he created a graph that purports to show the emissivity/absorbance of CO2 in gases at different temperatures. I made a post about how much heat went into a metre square column of air making the completely unsupported assumption that CO2 would absorb ALL the energy over a 12 hour night time period. I calculated the number of joules per second leaving the surface for the bandwidth of 13 to 17 microns, assuming again that black body levels apply. The result was a temperature increase of just 0.3C!!!!

Now look at the solar eclipse graph I posted and note that for just a 20% obscuration of the sun by the moon resulted in a loss of +2C degrees of air temperature! By the time totality was reached, 100% obscuration, air temperature had dropped by some 13 degrees over just 1 hour and 20 minutes. Yet surface temperature had only dropped about 5 degrees. And that was a pretty hot surface. Also note how quickly air temperature recovers as the moon exposes more and more of the sun. Note the RATE (slope) of recovery is steeper than the cooling. So there definitely is a delay in the rate the air loses temperature, but it is the SUN that warms the air, not the so called green house gases.
Environmentalism is based on lies and the lies reflect an agenda that regards humanity as the enemy of the Earth. - Alan Caruba
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#64
Thank you Richard111. I think this issue (is a watt timeless, or does it have a silent second in it) is one of the many dichotomies in physics. This is leading me down an interesting path..... One which will next have me posting my own version of a short definition of why a watt is timeless. Then all we have left is to fit a many sided whole (at least two sides) into a rounded whole explanation.... Confused, yup, me too. That is what I find fascinating, and what I want to try to get to the bottom of.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply
#65
I think I now have a solution to this apparent dilemma.

A Watt is defined as a joule per second, ie,
a watt IS a joule per second.

ie,
50 joules times 1 second is 50 Watts.
50 x 1 = 50
50 joules times zero seconds is 0 Watts.
50 x 0 = 0

A joule is an amount, a Watt is a rate of 1 joule per second.
A glass of water is an amount (like a joule is), the exact same glass of water emptied in one second is a rate of amount over a time period (like a watt is).
Amount with no time is an amount. Amount over time is a rate, a power, a flow.
Joule (amount)
Watt (amount / time)
Therefore a Watt without time is simply an amount, it is a joule, hence the definition of a Watt, that it IS a rate of a joule per second.

A Watt can be over any specified time period, as long as it is a period of time. If a time period is not specified, then by default (as the derived unit of a Watt is part of the SI system) the time period is a second.
The whole aim of practical politics is to keep the populace alarmed
(and hence clamorous to be led to safety)
by menacing it with an endless series of hobgoblins, all of them imaginary.

H. L. Mencken.  

The hobgoblins have to be imaginary so that
"they" can offer their solutions, not THE solutions.
Reply




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