Advertisements
Advertisements
प्रश्न
Characteristic X-rays may be used to identify the element from which they are being emitted. Can continuous X-rays be used for this purpose?
Advertisements
उत्तर
Characteristic X-rays are emitted due to the transitions of electrons among different shells. The wavelength of the X-rays emitted in these transitions have definite value for a particular element. But continuous X-rays are emitted due to the conversion of kinetic energy of an electron into photon, which varies from collision to collision and is independent of material. Hence, continuous X-rays provide no information about the element from which they are being emitted.
APPEARS IN
संबंधित प्रश्न
Identify the part of the electromagnetic spectrum which is:
produced by bombarding a metal target by high speed electrons.
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 high energetic invisible electromagnetic waves which help in the study of the structure of crystals
Name the rays or waves of highest frequency .
Name of physical quantity which remains same for microwaves of wavelength 1 mm and UV radiations of 1600 Å in vacuum.
The energy of a photon of a characteristic X-ray from a Coolidge tube comes from
If the current in the circuit for heating the filament is increased, the cutoff wavelength
The short-wavelength limit shifts by 26 pm when the operating voltage in an X-ray tube is increased to 1.5 times the original value. What was the original value of the operating voltage?
(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
X-rays
| Gamma rays | D | C | Visible light | B | A |
The above table shows different parts of the electromagnetic spectrum.
(a) Identify the parts of the spectrum marked as A, B, C and D.
(b) Which of the radiations A or B has the higher frequency?
(c) State two properties which are common to all parts of the electromagnetic spectrum.
(d) Name one source of each of the radiation of electromagnetic spectrum.
(e) Name one detector for each of the radiation.
(f) Name one use of each of the radiation.
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.
How will you investigate the existence of the radiation beyond the red and violet extremes of the spectrum?
What are the ultraviolet rays?
A bat moving at 10 ms−1 towards a wall sends a sound signal of 8000 Hz towards it. On reflection, it hears a sound of frequency f The value of f in Hz is close to (speed of sound = 320 ms−1)
The ozone layer absorbs
Ozone layer above the earth's atmosphere will
The half-value thickness of an absorber is defined as the thickness that will reduce exponentially the intensity of a beam of particles by a factor of 2. The half-value thickness in (µm) for lead assuming X-ray beam of wavelength 20 pm, µ = 50 cm-1 for X-rays in lead at wavelength λ = 20 pm, is ______ µm.
Which one of the following electromagnetic radiation has the least wavelength?
Name the electromagnetic radiation whose frequency is 10 Hz.
Name two electromagnetic waves of wavelength smaller than that of violet light.
