Mặt trời là nguồn năng lượng phổ quát trong sinh quyển. TRONG các quá trình phản ứng tổng hợp hạt nhân xảy ra trong mặt trời, năng lượng vào vấn đề IS thay đổi, nào là thải ra vào không gian dưới dạng các hạt điện từ, bức xạ và sóng HAVING Cả hai thuộc tính. Phổ bức xạ điện từ ĐÃ hoặc phân bố bước sóng từ có bước sóng ngắn ( nm, g và x-quang) với bước sóng dài (1015 nm, sóng phát thanh dài). Khoảng 99% của bức xạ CN IS TRONG vùng bước sóng 300-4000 nm. | Photosynthesis LIGHT The Sun is the universal source of energy in the biosphere. During the nuclear fusion processes occurring in the Sun matter is changed into energy which is emitted into space in the form of electromagnetic radiation having both wave and particle properties. The electromagnetic radiation has a spectrum or wavelength distribution from short wavelength 1026 nm g- and x-rays to long wavelength 1015 nm long radio waves . About 99 of the Sun radiation is in the wavelength region from 300 to 4000 nm and it is called the broadband or total solar radiation. Within this broadband different forms of energy exist which can be associated with specific phenomena such as harmful and potentially mutagen ultraviolet radiation UV 100-400 nm sight visible light 400-700 nm and heat infrared radiation 700-4000 nm . The particles producing the electromagnetic waves are called photons or quanta. The energy of a photon or quantum can be expressed as hv where h is the Planck s constant X 10-34 J sec and V is the frequency of the photon. The frequency is in turn equal to cA-1 where c is the speed of light 3 X 108 m sec-1 and A is the wavelength of the photon in nanometres nm . According to this formula the shorter the photon wavelength the higher its energy for example the energy of one photon of 300 nm light is X 10-19 J the energy of one photon of 400 nm light is X 10-19 J the energy of one photon of 700 nm light is X 10-19 J and the energy of one photon of 4000 nm light is X 10-19 J. The energy of photons can also be expressed in terms of electron volts eV . Absorption of a photon can lead to excitation of an electron and hence of a molecule. This excited electron acquires potential energy capacity of producing chemical work measured in eV. An electron volt is the potential energy of 1 V gained by the excited electron which is equal to X 10-19 J. Thus the energy of one photon of 300 nm light is equal to eV the energy of one photon
