Advertisements
Advertisements
प्रश्न
50% of the X-rays coming from a Coolidge tube are able to pass through a 0.1 mm thick aluminium foil. If the potential difference between the target and the filament is increased, the fraction of the X-rays passing through the same foil will be
विकल्प
0%
< 50%
50 %
> 50%
Advertisements
उत्तर
> 50%
The penetrating power of X-rays varies directly with the accelerating potential of the electrons (V) or the energy of the X-rays. So, if the potential difference between the target and the filament is increased, the fraction of the X-rays passing through the foil will also increase.
APPEARS IN
संबंधित प्रश्न
Give a reason for the following:
It is necessary to use satellites for long-distance TV transmission. Why?
Why are infra-red waves often called heat waves? Explain.
State the approximate range of wavelength associated with the ultraviolet rays.
Which part of electromagnetic spectrum is used in radar systems?
An X-ray beam can be deflected
Find the maximum potential difference which may be applied across an X-ray tube with tungsten target without emitting any characteristic K or L X-ray. The energy levels of the tungsten atom with an electron knocked out are as follows.
| Cell containing vacancy | K | L | M |
| Energy in keV | 69.5 | 11.3 | 2.3 |
A free atom of iron emits Kα X-rays of energy 6.4 keV. Calculate the recoil kinetic energy of the atom. Mass of an iron atom = 9.3 × 10−26 kg.
(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 Ultraviolet rays
Answer briefly.
Does an ordinary electric lamp emit EM waves?
Answer briefly.
Give two uses of radio waves.
Solve the numerical problem.
The speed of light is 3 × 108 m/s. Calculate the frequency of red light of a wavelength of 6.5 × 10−7 m.
Ozone layer above the earth's atmosphere will
Find the photon energy in units of ev for electromagnetic wave if waves length 40 m. Given h = 6.63 × 10–34 J.
SONAR emits which of the following waves?
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 ______.
Identify the part of the electromagnetic spectrum which:
- produces the heating effect.
- is absorbed by the ozone layer in the atmosphere.
- is used for studying crystal structure.
Write any one method of the production of each of the above radiations.
Name two electromagnetic waves of wavelength smaller than that of violet light.
What is the nature of all electromagnetic waves?
How do the wavelengths and frequencies of microwaves compare with those of radio waves?
Where does infrared radiation lie relative to visible light?
