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प्रश्न
Electromagnetic waves with wavelength
- λ1 is used in satellite communication.
- λ2 is used to kill germs in water purifies.
- λ3 is used to detect leakage of oil in underground pipelines.
- λ4 is used to improve visibility in runways during fog and mist conditions.
- Identify and name the part of electromagnetic spectrum to which these radiations belong.
- Arrange these wavelengths in ascending order of their magnitude.
- Write one more application of each.
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उत्तर
a. (i) In satellite communications, microwave is widely used. Hence λ1, is the wavelength of microwave.
(ii) In water purifier, ultraviolet rays are used to kill germs. So, λ2 is the wavelength of UV rays.
(iii) X-rays are used to detect leakage of oil in underground pipelines. So, λ3 is the wavelength of X-rays.
(iv) Infrared rays are used to improve visibility on runways during fog and mist conditions. So, it is the wavelength of infrared waves.
b. Wavelength of X-rays < wavelength of UV < wavelength of infrared < wavelength of microwave.
⇒ λ3 < λ2 < λ4 < λ1
c.
| Radiation | Uses |
| γ-rays | Gives information on nuclear structure, medical treatment etc. |
| X-rays | Medical diagnosis and treatment study of crystal structure, industrial radiograph. |
| UV-rays | Preserve food, sterilizing the surgical instruments, detecting invisible writings, fingerprints etc. |
| Visible light | To see objects |
| Infrared rays | To treat, muscular strain from taking photography during the fog, haze etc. |
| Microwave and radio wave | In radar and telecommunication. |
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संबंधित प्रश्न
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(a) 21 cm (wavelength emitted by atomic hydrogen in interstellar space).
(b) 1057 MHz (frequency of radiation arising from two close energy levels in hydrogen; known as Lamb shift).
(c) 2.7 K [temperature associated with the isotropic radiation filling all space-thought to be a relic of the ‘big-bang’ origin of the universe].
(d) 5890 Å - 5896 Å [double lines of sodium]
(e) 14.4 keV [energy of a particular transition in 57Fe nucleus associated with a famous high resolution spectroscopic method (Mössbauer spectroscopy)].
If the earth did not have an atmosphere, would its average surface temperature be higher or lower than what it is now?
Name the phenomenon which shows the quantum nature of electromagnetic radiation.
Name the high energetic invisible electromagnetic waves which help in the study of the structure of crystals
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State Moseley's law
Which radiation is used for satellite communication?
What is the range of the wavelength of the following electromagnetic waves?
(a) Gamma rays.
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(b) transfers energy to it
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Given below in the left column are different modes of communication using the kinds of waves given in the right column.
| A. | Optical Fibre Communication |
P. | Ultrasound |
| B. | Radar | Q. | Infrared Light |
| C. | Sonar | R. | Microwaves |
| D. | Mobile Phones | S. | Radio Waves |
From the options given below, find the most appropriate match between entries in the left and the right column.
What is the wavelength range of electromagnetic radiation used in radio broadcast?
