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प्रश्न
The energy of a photon of a characteristic X-ray from a Coolidge tube comes from
पर्याय
the kinetic energy of the striking electron
the kinetic energy of the free electrons of the target
the kinetic energy of the ions of the target
an atomic transition in the target
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उत्तर
an atomic transition in the target
In an X-ray tube, electrons are emitted by the filament. These electrons are made to strike the filament by applying an electric field between the filament and the target. As a result of it, the kinetic energy of the electrons is lost to the target atoms. This energy is utilised by the target atoms to knock out an electron from the innermost shell. Consequently, the electron makes a transition from the higher energy state to this vacant shell. Due to this transition, the difference of energy of the two states gives photon of characteristic X-ray.
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संबंधित प्रश्न
Identify the part of the electromagnetic spectrum which is:
produced by bombarding a metal target by high speed electrons.
To which part of the electromagnetic spectrum does a wave of frequency 5 × 1019 Hz belong?
What physical quantity is the same for X-rays of wavelength 10−10 m, red light of wavelength 6800 Å and radiowaves of wavelength 500 m?
State an additional use of the X-rays waves
A wave has wavelength 50 Å.
- Name the wave.
- State its speed in vacuum.
- State its one use.
What is the range of the wavelength of the following electromagnetic waves?
(a) Gamma rays.
State the approximate range of wavelength associated with the ultraviolet rays.
Name two electromagnetic waves of frequency smaller than that of violet light. State one use of each.
In a Coolidge tube, electrons strike the target and stop inside it. Does the target get more and more negatively charged as time passes?
X-ray from a Coolidge tube is incident on a thin aluminium foil. The intensity of the X-ray transmitted by the foil is found to be I0. The heating current is increased to increase the temperature of the filament. The intensity of the X-ray transmitted by the foil will be
(a) zero
(b) < I0
(c) I0
(d) > I0
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.
(Use Planck constant h = 6.63 × 10-34 Js= 4.14 × 10-15 eVs, speed of light c = 3 × 108 m/s.)
An X-ray tube operates at 40 kV. Suppose the electron converts 70% of its energy into a photon at each collision. Find the lowest there wavelengths emitted from the tube. Neglect the energy imparted to the atom with which the electron collides.
(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 Microwaves
Name the scientist who discovered radio waves
Name three radiations and their wavelength range which are invisible and beyond the violet end of the visible spectrum.
State two properties of infrared radiations which differ from visible light.
Answer briefly.
Does an ordinary electric lamp emit EM waves?
Solve the numerical problem.
Calculate the frequency in MHz of a radio wave of wavelength 250 m. Remember that the speed of all EM waves in a vacuum is 3.0 × 108 m/s.
Find the photon energy in units of ev for electromagnetic wave if waves length 40 m. Given h = 6.63 × 10–34 J.
