Help


[permalink] [id link]
+
Page "Effective temperature" ¶ 3
from Wikipedia
Edit
Promote Demote Fragment Fix

Some Related Sentences

effective and temperature
Thus, a well-planned adobe wall of the appropriate thickness is very effective at controlling inside temperature through the wide daily fluctuations typical of desert climates, a factor which has contributed to its longevity as a building material.
For stars, in the absence of extensive observations at many wavelengths, it usually must be computed assuming an effective temperature.
Theory predicts that, owing to Altair's rapid rotation, its surface gravity and effective temperature should be lower at the equator, making the equator less luminous than the poles.
Between 70 K and room temperature, berkelium behaves as a Curie Weiss paramagnetic material with an effective magnetic moment of 9. 69 Bohr magnetons ( µ < sub > B </ sub >) and a Curie temperature of 101 K. This magnetic moment is almost equal to the theoretical value of 9. 72 µ < sub > B </ sub > calculated within the simple atomic L-S coupling model.
Certain bacteria, notably Pseudomonas syringae, are particularly effective at triggering frost formation, raising the nucleation temperature to about − 2 ° C.
The effect of the field in this case is to reduce the effective binding energy of the atom to the surface and to give, in effect, a greatly increased evaporation rate relative to that expected at that temperature at zero fields.
However, since the Earth reflects about 30 % of the incoming sunlight, the planet's effective temperature ( the temperature of a blackbody that would emit the same amount of radiation ) is about − 18 ° C, about 33 ° C below the actual surface temperature of about 14 ° C.
The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect.
By treating the star as an idealized energy radiator known as a black body, the luminosity L and radius R can be related to the effective temperature by the Stefan Boltzmann law:
This in turn causes the star to become more luminous ( from 1, 000 10, 000 times brighter ) and expand ; the degree of expansion outstrips the increase in luminosity, causing the effective temperature to decrease.
Triple point cells are so effective at achieving highly precise, reproducible temperatures, an international calibration standard for thermometers called ITS 90 relies upon triple point cells of hydrogen, neon, oxygen, argon, mercury, and water for delineating six of its defined temperature points.
But as the temperature of heated plasma rises, the resistance decreases and ohmic heating becomes less effective.
This is seen as a variation in effective temperature over the star: the polar temperature is near 10, 000 K, while the equatorial temperature is 7, 600 K. As a result, if Vega were viewed along the plane of its equator, then the luminosity would be about half the apparent luminosity as viewed from the pole.
In the early 1950s workers at Phillips Petroleum discovered that chromium catalysts are highly effective for the low temperature polymerization of ethylene, which launched a major industrial technologies.
The surface of a star is defined to have a temperature given by the effective temperature in the Stefan Boltzmann law.
By using a simple model for stellar atmospheres, assuming local thermal equilibrium in a plane parallel geometry and the Eddington approximation, the effective temperature of the sun can be shown to occur at an optical depth of 2 / 3.
The Sun's photosphere has a temperature between 4500 and 6000 K ( with an effective temperature of 5777 K ) and a density of about 2 kg / m < sup > 3 </ sup >; other stars may have hotter or cooler photospheres.

effective and bolometric
Both effective temperature and bolometric luminosity actually depend on the chemical composition of a star.

effective and luminosity
Alpha Arietis is radiating about 91 times the Sun's luminosity from its outer envelope at an effective temperature of 4, 480 K. This is cooler than the surface of the Sun, giving it the orange-hued glow of a K-type star.
In that situation the mass of the neutralizing positive charge carriers is nearly 1836 times smaller ( the proton to electron mass ratio ), while the radiation pressure on the positrons doubles the effective upward force per unit mass, so the limiting luminosity needed is reduced by a factor of ≈ 1836 / 2 = 918.
Evolution of the solar luminosity, Solar radius | radius and effective temperature compared to the present day Sun.
This enlarged atmosphere is radiating 390 times as much luminosity as the Sun from its outer atmosphere at an effective temperature of 4, 030 K. This heat gives the star the orange-hued glow of a K-type star.
It is radiating 1, 995 times the luminosity of the Sun at an effective temperature of 3, 842 K.
It shines with 45 times the Sun's luminosity at an effective temperature of 4, 810 K, giving it the orange-hued glow of a K-type star.
This term means that the luminosity of the star will stay relatively stable while the effective temperature increases, effectively migrating horizontally across the H-R diagram.
The spectrophotometric measurements will provide the detailed physical properties of each star observed, characterising their luminosity, effective temperature, gravity and elemental composition.
It is of apparent magnitude 3. 44, radiating 129 % of the luminosity of the Sun from its outer envelope at an effective temperature of 6, 087 K. It appears to be rotating at a leisurely rate, with a projected rotational velocity of.
It is radiating 5, 000 times as much luminosity as the Sun from its outer atmosphere at an effective temperature of 6, 350 K, which creates the yellow-white glow of an F-type star.
Gamma Corvi is radiating 1, 260 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 15, 900 K, giving it a blue-white hue.
Kappa Aquarii is radiating 60 times the Sun's luminosity from its outer envelope at an effective temperature of 4, 581 K, giving it the orange-hued glow of a K-type star.
It has about 3. 5 times the mass of the Sun and is radiating around 363 times the Sun's luminosity from its outer atmosphere at an effective temperature of 9, 960 K. At this heat, the star glows with a blue-white hue.
The effective temperature of a star is the temperature of a black body with the same luminosity per surface area () as the star and is defined according to the Stefan Boltzmann law.
Eta Ursae Majoris is radiating around 1, 350 times as much luminosity as the Sun from its outer atmosphere at an effective temperature of about 16, 823 K, giving it the blue-white hue of a B-type star.
It is radiating 1, 834 times as much luminosity as the Sun from its outer envelope at an effective temperature of 7, 268, giving it the yellow-white hued glow of an F-type star.
It is radiating around 123 times the luminosity of the Sun from its outer envelope at an effective temperature of 9, 260 K. This gives it a white hue typical of an A-class star.
It is radiating about 471 times as much luminosity as the Sun from its outer atmosphere at an effective temperature of 3, 930 K. This is cooler than the Sun, giving this star the orange-hued glow of a K-type star.
From this expanded envelope, it is radiating roughly 5, 000 times the luminosity of the Sun at an effective temperature of 4, 337 K. This temperature is cooler than the Sun, giving it the orange-hued glow of a K-type star.

effective and are
The most effective political inventions seem to make maximum use of natural harbors and are aware that restraining breakwaters can play only a minor part in the whole scheme.
Often it is recognized that all the details of the pattern may not be essential to the outcome but, because the pattern was empirically determined and not developed through theoretical understanding, one is never quite certain which behavior elements are effective, and the whole pattern becomes ritualized.
We have staved off a war and, since our behavior has involved all these elements, we can only keep adding to our ritual without daring to abandon any part of it, since we have not the slightest notion which parts are effective.
The existence of a community is a state of mind -- a conviction that goals and values are widely shared, that effective communication is possible, that mutual trust is reasonably assured.
The major areas of self-help are the following: ( A ) the effective mobilizing of resources.
and ( C ) to finance, for not more than three years beyond the end of said period, such activities as are required to correlate, coordinate, and round out the results of studies and research undertaken pursuant to this Act: Provided, That funds available in any one year for research and development may, subject to the approval of the Secretary of State to assure that such activities are consistent with the foreign policy objectives of the United States, be expended in cooperation with public or private agencies in foreign countries in the development of processes useful to the program in the United States: And provided further, That every such contract or agreement made with any public or private agency in a foreign country shall contain provisions effective to insure that the results or information developed in connection therewith shall be available without cost to the United States for the use of the United States throughout the world and for the use of the general public within the United States.
Solid blocks are recommended because hollow blocks would have to be filled with concrete to give effective protection.
These expenditures are estimated to be $12.1 billion, an increase of $187 million over 1960, reflecting additional longevity pay of career personnel, more dependents, an increased number of men drawing proficiency pay, and social security tax increases ( effective for the full year in 1961 compared with only 6 months in 1960 ).
Meanwhile, other air defense forces are being made effective, as described later in this message.
Only when the newest Mr. America or Mr. Universe discovers them and puts them into practice are we reacquainted with them and once again see how effective they really are.
In a new house, generous roof overhangs are a logical and effective solution.
As mentioned above, where families are concentrated in larger numbers, group controls seem strongest and most effective.
Lacking the respected and effective institutions that consensus helps provide, minority parties, such as the P.D.I. in 1957 and the progressive Istiqlal faction in 1958, clamor for elections when out of power, but are not at all certain they wish to be controlled by popular choice when in power.
What determines the morality, they state, is not the means used, but the motive In general, the means ( excluding abortion ) that prove most effective are considered the most ethical.
Although science has given us more effective materials, preparations from anise, castorbean, colchicum, nux vomica, mustard, fennel, and stramonium are familiar to many for the relief of human ailments.
Private business is more effective than government aid, he explained, because individuals are able to work with the people themselves.
However, one can argue that no such control is necessary as long as one pretends that the anti-trust laws are effective and rational.
Quite clearly the anti-trust laws are neither effective nor rational -- and yet the argument goes that they should be extended to the labor union.
Workshops are conducted by the system's audio-visual consultant for the staffs of member libraries, teaching them the effective use of film as a library service.
The Protestant themselves are the first to admit the great falling off in effective membership in their churches.
Obviously what we are confronted with here is the identification of `` professional '' with narrow skills and specialization, the effective servicing of a client, rather than responsiveness to the wider and deeper meaning and associations of one's work.
In particular, this applies where large numbers of amateur astronomers with small telescopes are more effective than the relatively small number of large telescopes that are available to professional astronomers.

0.217 seconds.