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प्रश्न
Give one use of ultraviolet radiation.
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उत्तर
Ultraviolet radiations are used for detecting the purity of gems, eggs, ghee etc.
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संबंधित प्रश्न
Identify the part of the electromagnetic spectrum which is suitable for radar system used in aircraft navigation.
Name the phenomenon which shows the quantum nature of electromagnetic radiation.
Give one use of microwaves.
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- λ1 is suitable for radar systems used in aircraft navigation.
- λ2 is used to kill germs in water purifiers.
- λ3 is used to improve visibility in runways during fog and mist conditions.
Identify and name the part of the electromagnetic spectrum to which these radiations belong. Also arrange these wavelengths in ascending order of their magnitude.
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- Identify the electromagnetic waves.
- Write one source for each of them.
Identify the electromagnetic wave whose wavelength range is from about 10-3 m to about 10-1 m. Write one use of this.
In an atom X, electrons absorb the energy from an external source. This energy “excites” the electrons from a lower-energy level to a higher-energy level around the nucleus of the atom. When electrons return to the ground state, they emit photons.
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?
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