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NATURE OF LIGHT
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Photon
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| 1. Photon is a particle that has no mass
& no charge. 2. Rest mass of photon is zero. 3. Photons are the carriers of electromagnetic radiation . 4. Photons have very high frequency. 5. Energy of photon is E=hn . Where h = Planck's constant (h = 6.625 x 10 -34 j.s) and n = Frequency of radiation |
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Dispersion of light
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| “Splitting of light into its constituent
colors is known as dispersion of light” Light is a combination of seven colors. When light through any source is passed through a prism, it split into its component seven color and forms a spectrum of color like RAINBOW. This phenomenon is called “dispersion of light” |
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| For latest information , free computer courses and high impact notes visit : www.citycollegiate.com | |||
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Emission of light by atoms
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| According to Bohr’s atomic theory electrons
move around the nucleus is fixed orbits without radiating energy. However,
when an atom absorbs energy, it becomes excited and electrons jump to higher
orbit. But this excited state is unstable & electron jumps back to ground
level. In doing so they radiate energy in the form of light. This energy
is equal to the difference of energy between two orbits The energy of photon depends upon the energy difference between two orbits. Frequency of light depends upon the nature of atom. The frequency of radiation emitted together from a spectrum known as BRIGHT LINE SPECTRUM. Every element has its own characteristic spectrum. |
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| ................... ....Atom ...............................Absorption of energy........................Emission of energy | |||
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Spectrum
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| When light from any source is passed through a prism, it split into different color and a band of seven colors is obtained. This band of color is called spectrum | |||
| For latest information , free computer courses and high impact notes visit : www.citycollegiate.com | |||