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प्रश्न
The small ozone layer on top of the stratosphere is crucial for human survival. Why?
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उत्तर
The small ozone layer on the top of the atmosphere is crucial for human survival because it absorbs harmful ultraviolet radiations present in sunlight and prevents it from reaching the Earth’s surface.
संबंधित प्रश्न
Why are microwaves considered suitable for radar systems used in aircraft navigation?
If the earth did not have atmosphere, would its average surface temperature be higher or lower than what it is now? Explain.
Give a reason for the following:
It is necessary to use satellites for long-distance TV transmission. Why?
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Name the waves of wavelength nearly 0.1 nm.
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(Use Planck constant h = 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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Answer briefly.
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- λ2 is used to kill germs in water purifiers.
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Identify and name the part of the electromagnetic spectrum to which these radiations belong. Also arrange these wavelengths in ascending order of their magnitude.
Name two electromagnetic waves of wavelength smaller than that of violet light.
