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प्रश्न
Answer briefly.
Name the most harmful radiation entering the Earth's atmosphere from outer space.
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उत्तर
Name the most harmful radiation entering the Earth's atmosphere from outer space – Ultraviolet radiation
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संबंधित प्रश्न
Why are microwaves considered suitable for radar systems used in aircraft navigation?
How are infrared waves produced?
To which part of the electromagnetic spectrum does a wave of frequency 5 × 1019 Hz belong?
State Moseley's law
Name the region beyond the violet end of the spectrum called.
State the approximate range of wavelength associated with the ultraviolet rays.
Give one use of gamma rays.
Name the rays or waves of highest frequency .
Can X-rays be used for photoelectric effect?
X-ray incident on a material
(a) exerts a force on it
(b) transfers energy to it
(c) transfers momentum to it
(d) transfers impulse to it.
The Kα and Kβ X-rays of molybdenum have wavelengths 0.71 A and 0.63 A respectively. Find the wavelength of Lα X-ray of molybdenum.
The wavelengths of Kα and Lα X-rays of a material are 21.3 pm and 141 pm respectively. Find the wavelength of Kβ X-ray of the material.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
Name the scientist who discovered Infra-red waves
Name the scientist who discovered Ultraviolet rays
Name the part of the electromagnetic spectrum which is:
Produced by bombarding a metal target with high electrons.
Identify the part of the electromagnetic spectrum used in (i) radar and (ii) eye surgery. Write their frequency range.
Name the radiations used for the detection of fracture in bones.
Answer briefly.
Does an ordinary electric lamp emit EM waves?
Answer briefly.
What are radio waves?
Answer briefly.
Give two uses of radio waves.
An e.m. wave exerts pressure on the surface on which it is incident. Justify.
X-rays, gamma rays and microwaves travelling in a vacuum have ______.
Find the photon energy in units of ev for electromagnetic wave if waves length 40 m. Given h = 6.63 × 10–34 J.
Radio waves of constant amplitude can be generated with.
If λv, λx and λm Am represents the wavelength of visible light, x-ray and microwaves respectively, then ______.
One requires 11eV of energy to dissociate a carbon monoxide molecule into carbon and oxygen atoms. The minimum frequency of the appropriate electromagnetic radiation to achieve the dissociation lies in ______.
Electromagnetic waves with wavelength
- 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.
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.
Identify the electromagnetic wave whose wavelength range is from about 10-3 m to about 10-1 m. Write one use of this.
What happens when an electron collides with a positron?
