Advertisements
Advertisements
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
APPEARS IN
संबंधित प्रश्न
What role dose infra-red radiation play in physical therapy?
Why are infra-red waves often called heat waves? Explain.
The wavelengths for the light of red and blue colours are roughly 7.8 × `10^7` m and 4.8 × `10^7` m respectively.
(a) Which colour has the greater speed in vacuum?
(b) Which colour has the greater speed in glass?
Name the region beyond the red end of the spectrum.
Name the region beyond the violet end of the spectrum called.
What do you understand by the invisible spectrum?
State the approximate range of wavelength associated with infrared rays.
Give one use of microwaves.
Give one use of gamma rays.
In a Coolidge tube, electrons strike the target and stop inside it. Does the target get more and more negatively charged as time passes?
Can a hydrogen atom emit characteristic X-rays?
The energy of a photon of a characteristic X-ray from a Coolidge tube comes from
Consider a photon of continuous X-ray and a photon of characteristic X-ray of the same wavelength. Which of the following is/are different for the two photons?
The Kα X-rays of aluminium (Z = 13) and zinc (Z = 30) have wavelengths 887 pm and 146 pm respectively. Use Moseley's law √v = a(Z − b) to find the wavelengths of the Kα X-ray of iron (Z = 26).
(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.
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.)
The distance between the cathode (filament) and the target in an X-ray tube is 1.5 m. If the cutoff wavelength is 30 pm, find the electric field between the cathode and the target.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
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.
To which regions of the electromagnetic spectrum do the following wavelengths belong:
(a) 250 nm
(b) 1500 nm
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
State three properties of infrared radiations similar to that of visible light.
State three properties of ultra-violet radiation similar to visible light.
Give one use of electromagnetic radiation in Microwaves.
Answer briefly.
What are radio waves?
If λv, λx and λm Am represents the wavelength of visible light, x-ray and microwaves respectively, then ______.
Write two uses of the following radiation.
X-rays
Photons of an electromagnetic radiation has an energy 11 keV each. To which region of electromagnetic spectrum does it belong?
