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Micro / Macro numbers in Physics and Chemistry :
Planck's Constant :
Last edited by Jai Ganesh (2015-10-17 15:09:27)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Electron Rest Mass :
kilograms.Boltzmann Constant :
.Charge of an Electon :
Last edited by Jai Ganesh (2015-10-27 12:11:25)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Last edited by Jai Ganesh (2015-10-19 15:50:47)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Gravitational Constant
.Last edited by Jai Ganesh (2015-10-26 19:53:28)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Standard acceleration due to gravity, in vaccum
near of the surface of the earth.Last edited by Jai Ganesh (2015-10-19 16:14:13)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Please add speed of light, fine structure constant and gas constant too
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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Certainly, comrade... In a few hours...
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Online
Velocity of light :
.It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Online
Gas constant :
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Heaviest Metal : Osmium : Density :
Last edited by Jai Ganesh (2015-10-20 14:48:22)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Lightest gas : Hydrogen : Density at STP : 0 degrees Centigrade and 101.325 kPa :
Second lightest gas : Helium : Density at STP : at 0 degrees Centigrade and 101.525 kPa :
Last edited by Jai Ganesh (2015-10-20 15:25:09)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Planetary Data Distance Table
Planet : Distance (from Sun) : Diameter
Mercury : 57,910,000 km :0.387 A.U. : 4,800 km
Venus : 108,200,000 km : 0.723 A.U. : 12,100 km
Earth : 149,600,000 km : 1.000 A.U : 12,750 km
Mars : 227,940,000 km : 1.524 A.U. : 6,800 km
Jupiter : 778,330,000 km : 5.203 A.U. : 142,800 km
Saturn : 1,424,600,000 km : 9.523 A.U.: 120,660 km
Uranus : 2,873,550,000 km: 19.208 A.U. : 51,800 km
Neptune : 4,501,000,000 km : 30.087 A.U. : 49,500 km
Pluto : 5,945,900,000 km : 39.746 A.U. : 3,300 km
Last edited by Jai Ganesh (2015-10-26 20:03:11)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Helium gas has a density of 0.164g/liter It is 0.139 times as dense as air.
Air has a density of 1.18g/liter.
Material : Specific Gravity
Balsa wood : 0.2
Oak wood : 0.75
Ethanol : 0.78
Water : 1
Table salt : 2.17
Aluminium: 2.7
Iron : 7.87
Copper : 8.96
Lead : 11.35
Mercury : 13.56
Depleted uranium : 19.1
Gold : 19.3
Osmium : 22.59
(Samples may vary, and these figures are approximate.)
Urine normally has a specific gravity between 1.003 and 1.035.
Blood normally has a specific gravity of ~1.060.
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
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Heat capacity or thermal capacity is a measurable physical quantity equal to the ratio of the heat added to (or removed from) an object to the resulting temperature change. The SI unit of heat capacity is joule per kelvin
and the dimensional form is . Specific heat is the amount of heat needed to raise the temperature of a certain mass 1 degree Celsius.Last edited by Jai Ganesh (2015-10-23 15:11:04)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Mass heat capacity of building materials
(Usually of interest to builders and solar designers)
Mass heat capacity of building materials Substance : Phase : cP :
Last edited by Jai Ganesh (2015-10-23 16:05:10)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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In optics the refractive index or index of refraction n of an optical medium is a dimensionless number that describes how light, or any other radiation, propagates through that medium. It is defined as. where c is the speed of light in vacuum and v is the phase velocity of light in the medium.
Some representative refractive indices Material : λ (nm) : n
Vacuum : 1 (by definition)
Air at STP : 1.000277
Gases at 0 °C and 1 atm
Air : 589.29 : 1.000293
Carbon dioxide : 589.29 : 1.00045
Helium : 589.29 : 1.000036
Hydrogen 589.29 : 1.000132
Liquids at 20 °C
math trisulfide and sulfur in methylene iodide : 1.9
Benzene : 589.29 : 1.501
Carbon disulfide :589.29 : 1.628
Carbon tetrachloride : 589.29 : 1.461
Ethanol (ethyl alcohol) : 589.29 : 1.361
Silicone oil : 1.336-1.582
Water : 589.29 : 1.3330
10% Glucose solution in water : 589.29 : 1.3477
20% Glucose solution in water : 589.29 : 1.3635
60% Glucose solution in water : 589.29 : 1.4394
Solids at room temperature
Titanium dioxide (rutile phase) :589.29 : 2.614
Diamond : 589.29 : 2.419
Strontium titanate : 589.29 : 2.41
Amber : 589.29 : 1.55
Fused silica (also called fused quartz) : 589.29 : 1.458
Sodium chloride : 589.29 : 1.544
Other materials
Liquid helium : 1.025
Water ice : 1.31
Cornea (human) : 1.373/1.380/1.401
Lens (human) : 1.386 - 1.406
Acetone : 1.36
Ethanol : 1.36
Glycerol : 1.4729
Bromine : 1.661
Polytetrafluoroethylene (Teflon AF) : 1.315
Polytetrafluoroethylene (Teflon) : 1.35 - 1.38 :
Cytop : 1.34
Sylgard 184 (polydimethylsiloxane) : 1.4118
Polylactic acid :1.46
Acrylic glass : 1.490 - 1.492
Polycarbonate : 1.60
Poly(methyl methacrylate) (PMMA) : 1.4893 - 1.4899
PETg : 1.57
Polyethylene terephthalate (PET) : 1.5750
Kerosene : 1.39
Crown glass (pure) : 1.50 - 1.54
Flint glass (pure) : 1.60 - 1.62
Crown glass (impure) : 1.485 - 1.755
Flint glass (impure) : 1.523 - 1.925
Pyrex (a borosilicate glass) : 1.470
Cryolite : 1.338
Halite (rock salt) : 1.516
Sapphire : 1.762–1.778
Sugar solution, 25% : 1.3723
Sugar solution, 50% : 1.4200
Sugar solution, 75% : 1.4774
Cubic zirconia : 2.15 - 2.18
Potassium niobate (KNbO3) : 2.28
Silicon carbide (moissanite) : 2.65 - 2.69
Cinnabar (mercury sulfide) : 3.02
Gallium(III) phosphide : 3.5
Gallium(III) math :3.927
Zinc oxide : 390 : 2.4
Germanium 3000 - 16000 4.05 - 4.01
Silicon 1200 - 8500 3.48 - 3.42
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Table of Specific Heats for Various Substances
Substance
Air (50 degrees C) : 1046 : 0.250
Aluminum, Al : 900 : 0.215
Benzene, C6H6 : 1750 : 0.418
Copper, Cu : 387 : 0.0924
Glass : 837 : 0.200
Gold, Au : 130 : 0.0310
Ice, H2O (-10 degrees C to 0 degrees C) : 2093 : 0.500
Iron, Fe : 452 : 0.108
Lead, Pb : 128 : 0.0305
Marble : 858 : 0.205
Methanol or methyl Alcohol, CH3OH : 2549 : 0.609
Mercury, Hg : 138 : 0.0330
Silver, Ag : 236 : 0.0564
Soil : 1046 : 0.250
Steam, H2O (100 degrees C) :2009 : 0.480
Water, H2O (0 degrees C to 100 degrees C) : 4186 : 1.000
Wood : 1674 : 0.400
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. A typical human eye will respond to wavelengths from about 390 to 700 nm. In terms of frequency, this corresponds to a band in the vicinity of 430–770 THz.
Color : Wavelength : Frequency : Photon energy
violet : 380–450 nm : 668–789 THz : 2.75–3.26 eV
blue : 450–495 nm : 606–668 THz : 2.50–2.75 eV
green :495–570 nm :526–606 THz : 2.17–2.50 eV
yellow : 570–590 nm : 508–526 THz : 2.10–2.17 eV
orange : 590–620 nm : 484–508 THz : 2.00–2.10 eV
red : 620–750 nm : 400–484 THz : 1.65–2.00 eV
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Tables
In the standard atmosphere:
T0 is 273.15 K (= 0 °C = 32 °F), giving a theoretical value of 331.3 m/s (= 1086.9 ft/s = 1193 km/h = 741.1 mph = 644.0 kn). Values ranging from 331.3-331.6 may be found in reference literature, however;
T20 is 293.15 K (= 20 °C = 68 °F), giving a value of 343.2 m/s (= 1126.0 ft/s = 1236 km/h = 767.8 mph = 667.2 kn);
T25 is 298.15 K (= 25 °C = 77 °F), giving a value of 346.1 m/s (= 1135.6 ft/s = 1246 km/h = 774.3 mph = 672.8 kn).
In fact, assuming an ideal gas, the speed of sound c depends on temperature only, not on the pressure or density (since these change in lockstep for a given temperature and cancel out). Air is almost an ideal gas. The temperature of the air varies with altitude, giving the following variations in the speed of sound using the standard atmosphere—actual conditions may vary.
Effect of temperature on properties of air Temperature
T (°C) : Speed of sound
c (m/s) : Density of air
ρ (kg/cubic meters) : Characteristic specific acoustic impedance
z0 (Pa·s/m)
35 : 351.88 : 1.1455 : 403.2
30 : 349.02 : 1.1644 : 406.5
25 : 346.13 : 1.1839 : 409.4
20 : 343.21 : 1.2041 : 413.3
15 : 340.27 : 1.2250 : 416.9
10 : 337.31 : 1.2466 : 420.5
5 : 334.32 : 1.2690 : 424.3
0 : 331.30 : 1.2922 : 428.0
−5 : 328.25 : 1.3163 : 432.1
−10 : 325.18 : 1.3413 : 436.1
−15 : 322.07 : 1.3673 : 440.3
−20 : 318.94 : 1.3943 : 444.6
−25 : 315.77 : 1.4224 : 449.1
Last edited by Jai Ganesh (2015-10-26 20:19:08)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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Modern classification
The modern classification system is known as the Morgan–Keenan (MK) classification. Each star is assigned a spectral class from the older Harvard spectral classification and a luminosity class using Roman numerals as explained below, forming the star's spectral type.
Harvard spectral classification
The Harvard classification system is a one-dimensional classification scheme using single letters of the alphabet, optionally with numeric subdivisions, to group stars according to their spectral characteristics. Main-sequence stars vary in surface temperature from approximately 2,000 to 50,000 K, whereas more-evolved stars can have temperatures above 100,000 K. Physically, the classes indicate the temperature of the star's atmosphere and are normally listed from hottest to coldest.
Class Effective temperature Conventional color description Actual apparent color Main-sequence mass
(solar masses) Main-sequence radius
(solar radii) Main-sequence luminosity
(bolometric) Hydrogen
lines Fraction of all
main-sequence stars
O ≥ 30,000 K blue blue ≥ 16 M☉ ≥ 6.6 R☉ ≥ 30,000 L☉ Weak ~0.00003%
B 10,000–30,000 K blue white blue white 2.1–16 M☉ 1.8–6.6 R☉ 25–30,000 L☉ Medium 0.13%
A 7,500–10,000 K white blue white 1.4–2.1 M☉ 1.4–1.8 R☉ 5–25 L☉ Strong 0.6%
F 6,000–7,500 K yellow white white 1.04–1.4 M☉ 1.15–1.4 R☉ 1.5–5 L☉ Medium 3%
G 5,200–6,000 K yellow yellowish white 0.8–1.04 M☉ 0.96–1.15 R☉ 0.6–1.5 L☉ Weak 7.6%
K 3,700–5,200 K orange pale yellow orange 0.45–0.8 M☉ 0.7–0.96 R 0.08–0.6 L☉ Very weak 12.1%
M 2,400–3,700 K red light orange red 0.08–0.45 M☉ ≤ 0.7 R☉ ≤ 0.08 L☉ Very weak 76.45%
The spectral classes O through M, as well as other more specialized classes discussed later, are subdivided by Arabic numerals (0–9), where 0 denotes the hottest stars of a given class. For example, A0 denotes the hottest stars in the A class and A9 denotes the coolest ones.
Fractional numbers are allowed; for example, the star Mu Normae is classified as O9.7. The Sun is classified as G2.
The solar mass (M☉) is a standard unit of mass in astronomy that is used to indicate the masses of other stars, as well as clusters, nebulae and galaxies. It is equal to the mass of the Sun, about two nonillion kilograms:
M☉ =
Solar radius is a unit of distance used to express the size of stars in astronomy equal to the current radius of the Sun:
The solar luminosity, L☉, is a unit of radiant flux (power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars. It is defined in terms of the Sun's output. One solar luminosity is
, or . This does not include the solar neutrino luminosity, which would add 0.023 L☉. The Sun is a weakly variable star, and its luminosity therefore fluctuates. The major fluctuation is the eleven-year solar cycle (sunspot cycle) that causes a periodic variation of about ±0.1%. Other variations over the last 200–300 years is thought to be much smaller than this.Last edited by Jai Ganesh (2015-10-24 12:50:35)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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The Sun in visible wavelength with filtered white light on 8 July 2014. Characteristic limb darkening and numerous sunspots are visible.
Observation data
Mean distance
from Earth :
Orbital characteristics
Mean distance from Milky Way core
28 × Earth
Escape velocity = (from the surface) 617.7 km/s = 55 × Earth
Temperature = Center (modeled):
Last edited by Jai Ganesh (2015-10-24 23:25:48)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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The speed of sound is the distance travelled per unit time by a sound wave propagating through an elastic medium. The SI unit of speed is the metre per second (m/s). In dry air at 20 °C, the speed of sound is 343.2 metres per second (1,126 ft/s). This is 1,236 kilometres per hour (768 mph; 667 kn), or a kilometre in 2.914 s or a mile in 4.689 s.
Sir Isaac Newton computed the speed of sound in air as 979 feet per second (298 m/s), which is too low by about 15%, but had neglected the effect of fluctuating temperature; that was later rectified by Laplace.
During the 17th century, there were several attempts to measure the speed of sound accurately, including attempts by Marin Mersenne in 1630 (1,380 Parisian feet per second), Pierre Gassendi in 1635 (1,473 Parisian feet per second) and Robert Boyle (1,125 Parisian feet per second).
In 1709, the Reverend William Derham, Rector of Upminster, published a more accurate measure of the speed of sound, at 1,072 Parisian feet per second. Derham used a telescope from the tower of the church of St Laurence, Upminster to observe the flash of a distant shotgun being fired, and then measured the time until he heard the gunshot with a half second pendulum. Measurements were made of gunshots from a number of local landmarks, including North Ockendon church. The distance was known by triangulation, and thus the speed that the sound had travelled could be calculated.
Practical formula for dry air
The approximate speed of sound in dry (0% humidity) air, in meters per second, at temperatures near 0 °C, can be calculated from
,
where
is the temperature in degrees Celsius (°C).In the standard atmosphere:
is 273.15 K (= 0 °C = 32 °F), giving a theoretical value of 331.3 m/s (= 1086.9 ft/s = 1193 km/h = 741.1 mph = 644.0 kn). Values ranging from 331.3-331.6 may be found in reference literature, however;
In fact, assuming an ideal gas, the speed of sound c depends on temperature only, not on the pressure or density (since these change in lockstep for a given temperature and cancel out). Air is almost an ideal gas. The temperature of the air varies with altitude, giving the following variations in the speed of sound using the standard atmosphere—actual conditions may vary.
Last edited by Jai Ganesh (2015-10-25 01:44:01)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Online
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Online
In SI units, thermal conductivity is measured in watts per meter kelvin
. The dimension of thermal conductivity is . These variables are (M)mass, (L)length, (T)time, and (Θ)temperature. In Imperial units, thermal conductivity is measured in BTU/(hr·ft⋅°F).Thermal Conductivity : k : W/(m K)
Material/Substance : Temperature :
Last edited by Jai Ganesh (2015-10-27 15:54:04)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
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The following table shows the latent heats and change of phase temperatures of some common fluids and gases.
Substance : Latent Heat Fusion kJ/kg :Melting Point °C : Latent Heat Vaporization kJ/kg : Boiling Point °C
Alcohol, ethyl : 108 : -114 : 855 : 78.3
Ammonia : 332.17 : -77.74 : 1369 : -33.34
Carbon dioxide :184 : -78 : 574 : -57
Helium : 21 : -268.93
Hydrogen(2) : 58 : -259 : 455 : -253
Lead : 23.0 : 327.5 : 871 : 1750
Nitrogen : 25.7 : -210 : 200 : -196
Oxygen : 13.9 : -219 : 213 : -183
Refrigerant R134a: -101 : 215.9 : -26.6
Toluene : 72.1 : -93 : 351 : 110.6
Turpentine : 293
Water : 334 : 0 : 2264.76 : 100
Last edited by Jai Ganesh (2015-10-26 16:31:07)
It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.
Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.
Online