Roentgen in 1985 properties of x ray i they travel in

This preview shows page 30 - 32 out of 60 pages.

Roentgen in 1985Properties of X-rayi. They travel in straight lineii. They are not affected by electric and magneticfieldiii. They affect photographic plateiv. They cause fluorescencev. They undergo reflection, diffraction andinterferenceProduction of X-raysA heated cathode emits electron by thermionicemission. The electrons strike the target at a veryhigh velocity. The collisions (between electrons andthe target ) cause excitation of tungsten atoms whichconsequently emits x-raysHard X-rays and Soft X-raysSoft x-raysSoft x-rays are those with longer wavelength andlower penetrating power than normal. Theyproduced by lowering the potential differencebetween the cathode and the anodeThey can onlypenetrate soft flesh and can be used to showmalignant growth in tissuesHard x-raysHard x-rays are those with short wavelength andhigh penetration power than the normal.They areproduced by increasing the potential differencebetween the cathode and the anode of the tubeTheyare capable of penetrating flesh but are absorbed bybones.X-ray spectrumQuality of X-rayThe quality of x-ray is a measure of its penetrationpower. The higher the penetration power the higherthe qualityIntensity of X-RayIntensity of x-ray is the energy radiated per unit timeper unit area by the x-ray. The intensity of x-ray isdetermined by the current of the hot filament whichalso depends on the temperature of the filament.Uses of X-rays1. They are used to locate fracture in the bone ofman2. They are used to determine the structure ofcrystals3. They are used to detect cracks in metals4They are used in agriculture to kill germs5. They are used in radiotherapyHazards from x-rays1. X-rays can cause cancer2. X-rays can cause skin burns
313. X-rays can cause mutation of cells4. X-rays can cause cataracts5. X-rays can tissue damage.Wave-particle duality conceptThis refers to the idea that light and matter (such asElectrons) have both wave and particle properties.The De Broglie EquationIn 1924 Louis de Broglie proposed that matter had awave nature.His famous equation links themomentum 'p' of a particle with its wavelength ' λ'Where λ=debroglie wavelength, h is the plank’sconstantExample 15. Calculate the de Broglie wavelength ofan electron in a beam produced by thermionicemission and accelerated from rest through a pd of3600 V.(e= 1.6 × 1019C,h= 6.63 × 1034J s,m9.11 × 1031 kg ) [Ans; 2.05 x10-11]Example 16. Calculate the de Broglie wavelengthof: (a)an electron moving at a speed of 3.2 × 106ms1(b )a proton moving at the same speed.e =(e= 1.6 × 1019C,h= 6.63× 1034J s,me = 9.11 ×1031kg,mp = 1.67 × 1027kg )Example 17. Calculate the speed and de Brogliewavelength of an electron in an electron beam thathasbeen accelerated from rest through a pd of 2800 V.

Upload your study docs or become a

Course Hero member to access this document

Upload your study docs or become a

Course Hero member to access this document

End of preview. Want to read all 60 pages?

Upload your study docs or become a

Course Hero member to access this document

Term
Spring
Professor
ARKOSA
Tags
Magnetic Field, Electromagnetic induction, Lenz, D Fleming

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture