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16. In an electronic transisation, atom cannot emit _________ a. γ - rays b. Infrared radiation c. Visible light d. Ultraviolet rays 17. Reverse process of photo electric effect is __________ a. Pair production b. Compton effect c. Animation of matter d. X-rays production
18. X - rays are similar in nature to _______ a. Cathode rays b. Positive rays c. γ - rays d. α - rays 19. The penetrating power of X-ray depends on their ____________ a. Applied voltage b. Frequency c. Source d. All of the above 20. When X-rays are passed through successive aluminum sheets, what happens to their thickness? a. In increases b. It decreases c. Remains same d. Sometimes increase sometimes decreases 21. The penetrating power of X-rays is comparable with that of __________ a. α - rays b. β - rays c. γ - rays d. All of above
22. Quality of X-rays depends upon _______ a. Filament current b. Accelerating voltage c. Material of the target d. b and c 23. Radiation produced from T.V. picture tube is _________ a. γ - rays b. X - rays c. Far infrared d. Infrared 24. In an X - ray tube, electrons each of charge e are accelerated through V potential difference allowed to hit a metal target, the wavelength of the X-rays emitted is ____ a. hc/ev b. he/vc c. ev/h d. impossible to predict 25. The minimum wavelength of X-rays can
further be reduced by _________ a. Reducing the pressure of cooling the target b. Increasing the temperature of the filament c. Using a target element of higher atomic number d. Increasing the potential difference b/w the cathode and the target 26. The characteristic X-rays spectrum is due to ____ a. The illumination of the target metal by ultraviolet radiation b. The bombardment of the target by proton c. The bombardment of target by electron d. The absorption of Y-radiation by the target metal 27. The minimum wavelength of X-rays produced by the bombardment of electron on the screen of a T.V. set where the accelerating potential is 2.0 K,V will be ________ a. 6.2 x 10-10m b. 9.1 x 10-18m c. 3.11 x 10-10m d. 4 x 10-10m28. Maximum frequency in the spectrum
from x-rays tube is directly proportional to the ___________ a. Number of electron i.e. filament current b. The kinetic energy of incident electron c. The soft target which can easily emit electron d. All the above are correct 29. X-rays are diffracted by a crystal but not by a diffraction grating because ______ a. The ions in a crystal are well arranged b. The lines in a diffraction grating cannot reflect X-rays c. The perpetrating power of x-rays is which in a diffraction grating d. The wavelengths of x-rays are of same order of magnitude as the separation between atoms in a crystal