أشعة كهرومغناطيسية ( electromagnetic ) لها طول موجه قصير يتراوح ما بين 200 – 400 نانوميتر وموجودة بالمنطقة الزرقاء في طيف الضوء المرئي ( طول موجة الضوء المرئي يتراوح ما بين 400- 700 نانوميتر ) . تزداد كثافة الأشعة فوق البنفسجية كلما ارتفعنا عن سطح البحر ، فهي تبلغ نحو …
أكمل القراءة »absorption spectrum
absorption spectrum a spectrum produced when electromagnetic radiation is absorbed by a sample. The frequencies of the radiation absorbed are those able to excite the atoms or molecules of the sample from their ground states to excited states. The frequency, ν, at which a particular absorption line occurs depends on …
أكمل القراءة »Nature of light and electromagnetic spectrum
Nature of light and electromagnetic spectrum: According to Newton’s corpuscular theory, light is propagated as a stream of particles, called corpuscles. This could justify the phenomenon of reflection and refraction of light but failed to explain the phenomenon of diffraction, interference etc. Clerk Maxwell suggested that light waves are associated …
أكمل القراءة »absorption coefficient
1. (in spectroscopy) The molar absorption coefficient (symbol ε ) is a quantity that characterizes the absorption of light (or any other type of electromagnetic radiation) as it passes through a sample of the absorbing material. It has the dimensions of 1/{concentration x length). e is dependent on the frequency …
أكمل القراءة »Nature of light and electromagnetic spectrum
According to Newton’s corpuscular theory, light is propagated as a stream of particles, called corpuscules. This could justify the phenomenon of reflection and refraction of light but failed to explain the phenomenon of diffraction, interference etc. Clerk Maxwell suggested that light waves are associated with both electric and magnetic fields …
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