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प्रश्न
Give a reason for the following:
Long-distance radio broadcasts use short-wave bands. Why?
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उत्तर
Long distance radio broadcasts use shortwave bands because only these bands can be refracted by the ionosphere.
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संबंधित प्रश्न
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used as a diagnostic tool in medicine.
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Use the formula λm T= 0.29 cm K to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain tell you?
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(b) Which of the radiation mentioned by you in part (a) has the highest penetrating power.
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(a)X-rays,
What is the range of the wavelength of the following electromagnetic waves?
(a) Ultraviolet
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| Gamma rays | D | C | Visible light | B | A |
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(b) Which of the radiations A or B has the higher frequency?
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State three properties of infrared radiations similar to that of visible light.
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Choose the correct option.
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Answer briefly.
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Answer briefly.
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The ozone layer absorbs
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If λv, λx and λm Am represents the wavelength of visible light, x-ray and microwaves respectively, then ______.
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Electromagnetic waves with wavelength
- λ1 is used in satellite communication.
- λ2 is used to kill germs in water purifies.
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- λ4 is used to improve visibility in runways during fog and mist conditions.
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- Arrange these wavelengths in ascending order of their magnitude.
- Write one more application of each.
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