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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
The wavelengths for the light of red and blue colours are roughly 7.8 × `10^7` m and 4.8 × `10^7` m respectively.
(a) Which colour has the greater speed in vacuum?
(b) Which colour has the greater speed in glass?
What is the range of the wavelength of the following electromagnetic waves?
(a) Micro waves .
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Two waves A and B have wavelength 0.01 Å and 9000 Å respectively.
- Name the two waves.
- Compare the speeds of these waves when they travel in vacuum.
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,
Name the part of the electromagnetic spectrum which is:
Produced by bombarding a metal target with high electrons.
How will you investigate the existence of the radiation beyond the red and violet extremes of the spectrum?
Name two sources of infrared radiation.
The area to be covered for T.V telecast is doubled then the height of transmitting antenna (T.V tower) will have to be:-
Name two electromagnetic waves of wavelength smaller than that of violet light.
