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प्रश्न
Answer briefly.
Name the most harmful radiation entering the Earth's atmosphere from outer space.
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?
What role dose infra-red radiation play in physical therapy?
Which radiation is used for satellite communication?
A wave has a wavelength of 10-3 nm. Name the wave.
Give one use of microwaves.
Give one use of gamma rays.
Two waves A and B have wavelength 0.01 Å and 9000 Å respectively.
- Name the two waves.
- Compare the speeds of these waves when they travel in vacuum.
What are ultraviolet radiations?
Which part of electromagnetic spectrum is used in radar systems?
Is it possible that in a Coolidge tube characteristic Lα X-rays are emitted but not Kα X-rays?
Can a hydrogen atom emit characteristic X-rays?
An X-ray beam can be deflected
Consider a photon of a continuous X-ray coming from a Coolidge tube. Its energy comes from
What potential difference should be applied across an X-ray tube to get X-ray of wavelength not less than 0.10 nm? What is the maximum energy of a photon of this X-ray in joule?
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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.
Arrange the following electromagnetic waves in increasing order of their frequencies (i.e. begin with the lowest frequency):
Visible light, y rays, X rays, microwaves, radio waves, infrared radiations, and ultraviolet radiation.
Name the part of the electromagnetic spectrum which is:
Suitable for radar systems used in aircraft navigation.
Calculate the shortest wavelength of electromagnetic radiation present in Balmer series of hydrogen spectrum.
Name the radiation of the electromagnetic spectrum which is used for the following:
To photograph internal parts of the human body and Give the frequency range
Answer the following question.
Gamma rays and radio waves travel with the same velocity in free space. Distinguish between them in terms of their origin and the main application.
State two uses of infrared radiations.
What is the wavelength of the wave whose frequency is 1012 Hz? Name the electromagnetic wave.
Answer briefly.
Why are microwaves used in radar?
A car is moving towards a high cliff. The car driver sounds a horn of frequency f. The reflected sound heard by the driver has a frequency 2f. If v be the velocity of sound, then the velocity of the car, in the same velocity units, will be:
Following QN ∴ 14, the radiation force on the roof will be
A radio can tune to any station in the 7.5 mHz to 12 MHz band. What is corresponding wave length band.
In uranium (Z = 92) the K absorption edge is 0.107 Å and the Kα line is 0.126 Å, and the wavelength of the L absorption edge is ______.
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.
Which one of the following electromagnetic radiation has the least wavelength?
