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प्रश्न
Electromagnetic waves of wavelengths λ1, λ2 and λ3 are used in a radar system, in water purifiers and in remote switches of TV, respectively.
- Identify the electromagnetic waves.
- Write one source for each of them.
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उत्तर
(i)
- Wavelength λ1 corresponds to Microwaves.
- Wavelength λ2 corresponds to Ultraviolet waves.
- Wavelength λ3 corresponds to Infrared waves.
(ii)
- Source of microwaves: Klystron/magnetron valves.
- Source of ultraviolet waves: Movement of electrons in atoms from higher energy level to lower energy level.
- Source of infrared waves: Vibration of atoms and molecules.
संबंधित प्रश्न
Identify the part of the electromagnetic spectrum which is suitable for radar system used in aircraft navigation.
Give a reason for the following:
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Which radiation is used for satellite communication?
The figure shows the intensity-wavelength relations of X-rays coming from two different Coolidge tubes. The solid curve represents the relation for the tube A in which the potential difference between the target and the filament is VA and the atomic number of the target material is ZA. These quantities are VB and ZB for the other tube. Then,
Arrange the following electromagnetic waves in increasing order of their frequencies (i.e. begin with the lowest frequency):
Visible light, y rays, X rays, microwaves, radio waves, infrared radiations, and ultraviolet radiation.
Give one use of electromagnetic radiations in Infrared radiation.
Identify the electromagnetic wave whose wavelength range is from about 10-3 m to about 10-1 m. Write one use of this.
Which devices commonly produce microwaves?
How does the frequency of violet light compare with that of red light?
