Click here to see the latest start time for this test. The TSI Assessment is a college readiness test delivered through the Accuplacer system, specifically designed by the College Board to meet the requirements set forth by the Texas Legislature and the Texas Higher Education Coordinating Board (THECB).
7.2 The spectrum of the sun Visible light and infrared radiation constitute the major fraction of solar radiation reaching the atmosphere of the Earth (Fig. 7-1). Approximately 40 % of the radiation energy is visible light of wavelengths between 400 and 700 nm.. Visible Light and UV Radiation 75 Effects of the ozone layer Ozone, O 3, is produced when oxygen, O 2, in the upper atmosphere absorbs UVC (Î»). This absorption completely eliminates UVC from the solar radiation and dissociates oxygen molecules to oxygen atoms.
The sun is a major source of ultraviolet rays. Though the sun emits all of the different kinds of electromagnetic radiation, 99% of its rays are in the form of visible light, ultraviolet rays, and infrared rays (also known as heat).V-A rays do not have enough energy to break apart the bonds of the ozone, so UV-A radiation passes the earth's atmosphere almost unfiltered. As both UV-B and UV-A rays can be detrimental to our health, it is important that we protect ourselves.