X-rays was discovered by scientist Rontgen that's why they are also called Rontgen pulses.
Rontgen discovered that when pressure inside a discharge tube kept 10-3 mm of Hg and potential difference is 25 kV then some unknown radiations (X-pulses) are emitted by anode.
Production of X-rays
There are three essential needs for the production of X-rays
(i) A source of electron
(ii) An management to accelerate the electrons
(iii) A target of suitable metal of high atomic weight and high melting point on which these high speed electrons strike.
Depending upon the penetration power, X-rays are of two kinds:-
|
Hard X-rays
|
Soft X-rays
|
|
More penetration power
|
Less penetration power
|
|
More frequency of the order of » 1019 Hz
|
Less frequency of the order of » 1016 Hz
|
|
Lesser wavelength range (0.1Å - 4Å)
|
More wavelength range (4Å - 100Å)
|
Properties of X-rays:
(i) X-rays are electromagnetic waves with wavelength lie between 0.1Å - 100Å.
(ii) X-rays are invisible.
(iii) They go in a straight line with speed of light.
(iv) X-rays carry no charge so they are not deflected in magnetic field and electric field.
(v) 
(vi) They ionise the gases
(vii X-rays do not go through heavy metals and bones.
(viii) Long period of time to X-rays is injurious for human body.
(ix) For X-ray photography of human parts, BaSO4 is the great absorber.
(x) They give photoelectric effect and Compton Effect
(xi) These cannot be used in Radar due to they are not reflected by the target.
|
Absorption of X-rays: These rays are absorbed when they incident on object.
Intensity of emergent X-rays 
So intensity of absorbed X-rays 
wherem = absorption coefficient, x = thickness of absorbing medium
|
|
Classification of X-Rays
In X-ray tube, when high speed electrons strike the target, they penetrate the target. They lose their kinetic energy and come to rest inside the solid. The electron due to finally being stopped makes several collisions with the atoms in the target. At every collision one of the given two kinds of X-rays may get form.
|
Continuous X-rays: As an electron passes close to the positive nucleus of atom, the electron is moved from it's path as given in diagram. This results in deceleration of the electron. The loss in power of the electron in the mean while deceleration is emitted in the form of X-rays.
The X-ray photons emitted so form the continuous X-ray spectrum.
|
|
Minimum wavelength: When the electron looses whole of it's energy in a single collision with the atom, an X-ray photon of maximum energy hnmax is emitted i.e. 
where v = velocity of electron before collision with target atom, V = potential difference through which electron is accelerated, c = speed of light = 3 ´ 108 m/s
Maximum frequency of radiations (X-rays) 
Minimum wave length = cut off wavelength of X-ray 
|
If the electrons striking the target eject an electron from the K-shell of the atom, a vacancy is crated in the K-shell. Instantly an electron from one of the outer most shell, say L-shell jumps to the K-shell, emitting an X-ray photon of energy equal to the energy difference between the two shells. Similarly, if an electron from the M-shell jumps to the K-shell, X-ray photon of high power is emitted. The X-ray photons emitted due to the jump of electron from the L, M, N shells to the K-shells gives Ka, Kb, Kg lines of the K-series of the spectrum.
|
|
If the electron striking the target ejects an electron from the L-shell of the target atom, an electron from the M, N ..... shells jumps to the L-shell so that X-rays photons of lesser power are emitted. These photons form the smaller energy emission. These photons form the L-type of the spectrum. In a same way the formation of M type, N type etc. may be described.
Email based Physics assignment help - homework help at Expertsmind
Are you searching physics expert for help with X-Rays questions? X-Rays topic is not easier to learn without external help? We at www.expertsmind.com offer finest service of Physics assignment help and physics homework help. Live tutors are available for 24x7 hours helping students in their X-Rays related problems. We provide step by step X-Rays question's answers with 100% plagiarism free content. We prepare quality content and notes for X-Rays topic under physics theory and study material. These are avail for subscribed users and they can get advantages anytime.
Why Expertsmind for assignment help
- Higher degree holder and experienced experts network
- Punctuality and responsibility of work
- Quality solution with 100% plagiarism free answers
- Time on Delivery
- Privacy of information and details
- Excellence in solving physics queries in excels and word format.
- Best tutoring assistance 24x7 hours