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प्रश्न
If the earth did not have an atmosphere, would its average surface temperature be higher or lower than what it is now?
उत्तर
In the absence of an atmosphere, there would be no greenhouse effect on the surface of the Earth. As a result, the temperature of the Earth would decrease rapidly, making it chilly and difficult for humans to survive.
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संबंधित प्रश्न
Given below are some famous numbers associated with electromagnetic radiations in different contexts in physics. State the part of the electromagnetic spectrum to which each belongs.
(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)].
Name the phenomenon which shows the quantum nature of electromagnetic radiation.
What is the range of the wavelength of the following electromagnetic waves?
(a) Gamma rays.
Give one use of microwaves.
Name the rays or waves of highest frequency .
Name the waves of wavelength nearly 0.1 nm.
Name three properties of ultraviolet radiations which are similar to visible light.
Why is exposure to X-rays injurious to health but not exposure to visible light, when both are electromagnetic waves?
For harder X-rays,
(a) the wavelength is higher
(b) the intensity is higher
(c) the frequency is higher
(d) the photon energy is higher.
State the name and the range of wavelength of the invisible electromagnetic waves beyond the red end of the visible spectrum.
Name three radiations and their wavelength range which are invisible and beyond the violet end of the visible spectrum.
Name any two electromagnetic waves which have a frequency higher than that of violet light. State one use of each.
Name two sources of ultraviolet radiation.
Answer briefly.
Why high-frequency carrier waves are used for the transmission of audio signals?
Microwaves are electromagnetic waves with frequency in the range of.
The frequency of x-rays, y-rays and ultraviolet rays are respectively a, b and c. Then:-
The electric field intensity produced by the radiations coming from 100 W bulb at a 3 m distance is E. The electric field intensity produced by the radiations coming from 50 W bulb at the same distance is ______.
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.
Name the electromagnetic radiation whose frequency is 10 Hz.
