X-Rays Questions and Answers

4 Transfer characteristics output voltage Vo vs input voltage V for a base biased transistor in CE configuration is as shown in the figure For using transistor as a switch it is used 2012 II III N Vo a in region III b both in region I and III c in region II d in region I V

A p n photodiode is made of a material with a band gap of 2 0 eV The minimum frequency of the radiation that can be absorbed by the material is nearly a 10 10 4 Hz c 1 10 4 Hz The circuit 2008 b 5 10 4 Hz d 20 10 4 Hz 2008

A cobalt target is bombarded with electrons and a characteristic x ray spectrum is measured A second fainter characteristic spectrum is observed due to impurity in cobalt The wavelengths of the Ka lines are 178 9 pm cobalt and 143 5 pm impurity and the proton number for cobalt is 27 Determine the impurity element using only these data 3

Manufacturers of wire and other objects of small dimension sometimes use a laser to continually monitor the thickness of the product The wire intercepts the laser beam producing a diffraction pattern like that of a single slit of the same width as the wire diameter Fig 36 37 Suppose a helium neon laser of wavelength 632 8nm illuminates a wire and the diffraction pattern appears on a screen at distance L 2 60m If the desired wire diameter is 1 37mm what is the observed distance between the two tenth order minima one on each side of the central maximum Wire He Ne laser Figure 36 37 Problem 10 Wire making machine

2 When a free neutron decays to form a proton and an electron then choose the incorrect statement 1 The relation may be expressed as n p e v 2 Every electron comes out with the same energy 3 The electron shares the major part of the energy released 4 All the above 3 Photons of energy 6 eV are incident on a metal surface whose work function is 4 eV The minimum

Electrons of mass m with de Broglie wavelength A fall on the target in an X ray tube The cutoff wavelength 20 of the emitted X ray is NEET Phase 2 2016 1 20 3 20 2mc h 2m c 2 2 2 2h mc 4 2

In a p n Junction Diode a square input signal of 10V is applied as shown in the figure 5V HI R SV Then the output signal across R will be skipped B 5V n 10 V n QU MY F S

Electrostatic experiments do not work well on humid days because moist air conducts electricity A charged matellic body has same potential but the distribution of charge may or may not be uniform A small metal ball is suspended in a uniform electric field with the help of an insulated thread If a high ener X ray beam falls on the ball it will be deflected in the direction of the field

of How much energy will be released when 10 kg of U235 is completely converts into energy 1 5 x 1027 MeV 2 5 x 1024 MeV 3 9 x 1017 J 4 All of these much energy is released when 2 mole of U235

When the voltage applied to an X ray tube increased from V 15 5 KV to V 31 KV the wavelength interval between the Ka line and the short wavelength cut off of the continuous X ray spectrum increases by a factor of 1 3 Find the atomic number of the element of the target If your N answer is N fill value of Take hc 13 1240 eV nm and R 1 107m

5 Characteristic X rays are not obtained in the spectrum of H atom because 1 hydrogen is a gas 2 hydrogen is very light 3 energy difference in energy levels of hydrogen is much less 4 energy difference in energy levels of hydrogen is much high 1947

Ge and Si diodes conduct at 0 3 V and 0 7 V respectively In the following figure if Ge diode connection is reversed the value of V changes by 12VI 1 0 2 V Ge A Si 5k2 Vo 11 2 0 4 V

0 A small metallic ball is suspended in a uniform electric field with the help of an insulated thread If high energy X ray beam falls on the ball the ball will be deflected in the direction of the field 1983

1 The momentum a 13 26x10 26 of an X ray photon with 0 5 is kg m s b 1 326x10 26 kg m s kg m s c 13 26x10 24 d 13 26 x 10 22 kg m s

The wavelength of Ka X ray produced by a X ray tube is 0 76 The atomic number of the anode material of the tube is A 38 C 63 B 40 D 53

ALLEM reduce the ripples in a rectifier circuit with 13 capacitor filter a R should be increased b Input frequency should be decreased c Input frequency should be increased d Capacitors with high capacitance should be used 1 Only a 3 a b and d 2 Only a and b 4 a c and d The energy of radiation emitted by LED is 1 greater than the band gap of the semiconductor used 2 always less than the band gap of the semiconductor used 3 always equal to the band gap of the semiconductor used 4 equal to or less than the band gap of the semiconductor used In a common emitter transistor circuit the bas than V is