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प्रश्न
State three properties of ultra-violet radiation similar to visible light.
उत्तर
(i) Ultra-violet radiations can travel in vacuum as the visible light can do, with the speed 3 × 108 ms−1.
(ii) Both the ultra-violet radiations and the visible light are electromagnetic waves.
(iii) Both the ultra-violet radiations and the visible light obey the laws of reflection and refraction.
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संबंधित प्रश्न
To which part of the electromagnetic spectrum does a wave of frequency 5 × 1019 Hz belong?
Name the subjective property of light related to its wavelength.
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(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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The figure below is the energy level diagram of atom X with three energy levels, E1 = 0.00eV, E2 = 1.78eV and E3 = 2.95eV. The ground state is considered 0 eV for reference. The transition of electrons takes place between levels E1 and E2.
- What wavelength of radiation is needed to excite the atom to energy level E2 from E1?
- Suppose the external source has a power of 100 W. What would be the rate of photon emission?
