Showing posts with label SOLAR PHYSICS. Show all posts
Showing posts with label SOLAR PHYSICS. Show all posts

38 Facts About the Atmosphere


39 Facts about atmosphere describing atleast  one characteristic of each of the four main layers of the atmosphere
1.     Atmosphere is the layer of gas surrounding the earth.
2.     Temperature in the atmosphere varies with altitudes.
3.     The higher the altitudes the lesser the density of air.
4.     The troposphere is part of the atmosphere we live.
5.     The composition of air in the troposphere is nitrogen 78%, oxygen 21%, carbon dioxide 0.03% and the rest are inert gases and water vapor.
6.     The scattering of solar radiation by the air molecules is called molecular scattering.
7.     The scattering of dust particle, organic particles by the atmosphere is called particulate scattering.
8.     The atmosphere protects the earth and it’s living against harmful solar rays.
9.     The atmosphere maintains the earth temperature at moderate levels.
10.                  The thick layers of the atmosphere blocks gamma rays, cosmic rays from reaching the earth.
11.                  The thick atmospheric layers destroy meteors before reaching the earth.
12.                  Troposphere, stratosphere, chemosphere, ionosphere are layers of the atmosphere.
13.                  The troposphere is 0km to 11km above the earth surface.
14.                  Clouds and weather element are in the troposphere.
15.                  At the troposphere the higher you go the cooler it become.
16.                  The next layer after the troposphere is the stratosphere.
17.                  The stratosphere is within 11km to 48km upwards.
18.                  The ozone layer is in the stratosphere.
19.                  Green house gases are in the ozone layer.
20.                  The atmosphere provides warmth to the organisms within the earth.
21.                  Depletion of the ozone layer can cause global warming.
22.                  Destructive ultraviolet solar radiation is trapped by the ozone layer.
23.                  In the stratosphere the higher you go the hotter it becomes.
24.                  The highest temperature in the stratosphere is 0°c.
25.                  Mesosphere is the next layer after the stratosphere.
26.                  Mesosphere is a thin layer.
27.                  The atmosphere allows short solar waves to pass while blocking earthly long wavelength.
28.                  The atmosphere act like glass in a green house.
29.                  Carbon dioxide, methane, nitrogen oxide, chlorofluorocarbon and water vapor are cause of green house effects.
30.                  The stop global warming atmospheric intake of green house gases must be reduced.
31.                  Burning fossil fuels are responsible for increase in green house effect.
32.                  In the mesosphere the higher you go the cooler it becomes.
33.                  The highest temperature in the mesosphere is -90°c.
34.                  The next layer is the thermosphere.
35.                  The thermosphere is 55km above
36.                  It is high temperature layer about thousands of degrees.
37.                  Exosphere is a layer after the thermosphere.
38.                  Ionosphere is the sum of all region containing ions.



No comments:

41 Facts about thermal radiations


Facts about thermal radiations
1.     Most of the solar radiations reaching the earth are in the thermal radiation ranges.
2.     Thermal radiations are emitted as a result of  thermal agitations
3.     Thermal agitations are as a result of increase in temperature.
4.     Heat and light spectra of electromagnetic radiations falls under thermal radiations.
5.     Electromagnetic radiations with wavelength between 0.2 to 10000 micrometer are part of thermal radiations
6.     Thermal radiations are the visible light, ultra violet and the infrared portions.
7.     Thermal radiations can be divided into short wave and the long wave.
8.     The visible light is part of thermal radiations and falls with wavelength between 0.39 to 0.77micrometer.
9.     The intensity of solar radiation impinging on a surface depends on angle of incident, time of the year and atmospheric condition.
10.                        The infrared region is divided into near infra red and far infra red.
11.                        Emission of radiations is due to oscillations and transitions of electrons that comprise matter and is sustained by the thermal energy of the matter.
12.                        Emission correspond to heat transfer from the matter and hence a reduction in thermal energy stored by the matter.
13.                        Radiation may also be intercepted absorbed by matter.
14.                        Absorption of radiation result to heat transfer by the matter and hence an increase in energy stored by the matter.
15.                        Emission from gas or transparent liquid or solid is a volumetric phenomenon.
16.                        Emission from an opaque solid or liquid is a surface phenomenon.
17.                        For an opaque object emission from atoms and molecules within one micrometer depth to the surface.
18.                        All bodies emit radiations at temperature above 0k, absolute zero.
19.                        A transparent body will transmit all radiations that falls on it.
20.                        A translucent body will scatter radiation falling on it.
21.                         An opaque object will absorb or reflect radiation falling on it.
22.                        Scatting is the diffused reflection of light in a body.
23.                        The absorption and reflection of radiations depend on the color and size of the molecules of the object involved.
24.                        When a body absorb radiations it temperature rises and it start to emit radiations.
25.                        It is only a black body that can absorb or reflect all wavelength of light at temperature and all angles of incidence.
26.                        When wavelength of radiation is greater than size of atom or molecules a body the wave will be scattered.
27.                        Change in temperature in matter cause charge oscillations which in turn produce electromagnetic radiations.
28.                        Sunlight is part of electromagnetic radiations produced by the hot plasma of the sun.
29.            Absorptivity , reflectivity and emissivity of all objects depend on wavelength of radiations.
30.            The frequency of distribution of thermal radiations is given by plank’s law.
31.            Increase in the rate of thermal radiation is proportional to the 4th root of its temperature T4.
32.            Objects absorb much of the frequency range they can emit.
33.            The rate at which objects radiates (or absorb) depends on the nature of the surface.
34.            Object that is a good emitter is also a good absorber.
35.            The hotter an object is the more light it emits.
36.            Stephan-Boltzmann law states that the total energy radiated per unit surface area of a blackbody across all wavelengths per unit time is proportional to the fourth power of its absolute temperature.
37.            Emissivity is the measure of the effectiveness of emission of thermal radiation by a surface.
38.            Absorptivity of a surface is the measure of its effectiveness in absorption of radiations.
39.             The spectral distribution of radiation intensity is explained by plank’s law.
40.            Reflectivity is the ratio of the reflected to the incident radiation impinging a surface.
41.            Transmissivity is the ratio of transmitted to incident



No comments:

51 Sun Facts and Some Properties




Properties of the sun
1.     The sun is the centre of mass in the solar system.
2.     The sun is the centre of gravity in the solar system.
3.     The sun has a linear diameter of 1.39×106 km
4.     The sun has an angular velocity of about 3.2×106 km from east to south.
5.     The surface area of the sun is 6.09×1012km2  
6.     The sun has a mass of 1.99×1030kg
7.     The sun has a volume of 1.41×1027km3
8.     It has a mean density of  1400kg/m3
9.     It has a surface temperature of about 5538°C.
10.                        The temperature at the center is about 1.67×107°C.
11.                        It as a parabolic velocity at the surface of about 617 kilometer per hour.
12.                        The escape velocity at the surface is 11200m/s
13.                        Rotational velocity equatorial perspectives 465 m/s
14.                        Mean velocity 29.78km/s.
15.                        The period of revolution of sun around its galaxy is about 250 million years.
16.                         A light year is a distance travelled by light in a year which is about 10, 000 billion kilometers.
17.                        The sun has a radius of about 696, 000 km
18.                        Sun has a surface gravity of 274 m/s2
19.                         The distance between the sun and the earth is about 150 million kilometers.
20.                        The elemental composition hydrogen 74%, helium 25 % and others1% by mass.
21.                        The age of the sun is about4.5 billion years
22.                        The brightness of the sun is about 4.0×1033erg/s.
23.                        The sun is completely gaseous; there is no solid surface on the sun.
24.                        Solar cycle repeats after a period of 11 years.
25.                        The sun has about 99.8% of the total mass of the solar system.
26.                        The sun generates its energy by nuclear fusion reaction.
27.                         Its orbit from the center of its galaxy is about 25, 000 light years.
28.                        The sun belongs to the generation of stars called population 1.
29.                        The sun is at its closest distance to the earth of about 0.983 AU on about 3rd of January of every year.
30.                        AU is the astronomical unit equal 150 million kilometers.
31.                        The farthest distance from the earth of about 1.017AU on about 4th of July of every year.
32.                        The sun is at its average distance on the 5th of October and 4th of April.
33.                        The maximum solar declination in a day is 0.5°
34.                        Insolation or solar constant is the intensity of direct solar radiation incident on a horizontal surface per unit area per unit time.
35.                        Sun has an equatorial circumference of 4.379×106 kilometer.
36.                        It is 109 times larger than the earth and 330, 000 time massive than the earth.
37.                        The sun is so hot that no single solid or liquid can stay on it.
38.                        All planetary and interplanetary gravitational phenomena are negligible compared to that brought by the mass of the sun.
39.                        The sun is the primary source of energy on the earth.
40.                        Almost 75% of the sun mass is gaseous hydrogen.
41.                        The sun has enough fuel (hydrogen ) to survive another 4 billion years
42.                        The sun is brighter than 85% of the stars in the Milky Way.
43.                        The sun is 13 billion times brighter than the next brightest star.
44.                        The sun does not have an outer boundary, it density decrease exponentially as its distance decreases from the centre.
45.                        It takes 8 minutes 19 seconds for light from the sun horizon to reach the earth horizon.
46.                        The sun rotates faster at its equator than at its poles.
47.                        The sun is white in color, the yellow, red and magenta are due to the scattering of the sun ray by the atmosphere.
48.                        Perihelion the closest distance of the sun from the earth which is 0.983AU.
49.                        Aphelion is the farthest distance of the sun from the earth which is 1.017AU.
50.                        Solstice means unequal day and night, it occur when the solar declination angle is +23.5° or -23.5°.
51.                        Equinox means equal day and night, it occurs when solar declination angle is zero.
No comments: