D C B A a low intensity fast UV flash a macro lens UV sensitive film a tripod

D c b a a low intensity fast uv flash a macro lens uv

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D) C) B) A) a low intensity fast UV flash a macro lens UV sensitive film a tripod For colour photography of both visible and fluorescent indications it is recommended to use 257. D) C) B) A) "incandescent" film normal daylight film film with greater than 500 ASA speed none of the above, colour photography is not recommended for NDT purposes. Polarizing filters are used in MPI indication photography for what purpose? 258. D) C) B) A) to reduce highlights and reflections to remove infra-red light to remove orange light to intensify yellow-green light ESTestMaker Questions 43
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UV filters used in fluorescent indication photography ;are sometimes called 259. D) C) B) A) Kodak filters haze filters crossed nichols polarizing filters When photographing MPI indications it is often a good practice to expose extra frames using higher and lower f-stops to compensate for unforeseen conditions. This practice is called 260. D) C) B) A) "hedging your bets" betting to show bracketing full-stopping Which of the following is an advantage of video tape recording of MPI indications? 261. D) C) B) A) availability to do subsequent image enhancement cost ease and speed to produce both a and b The fact that only some magnetic domains resume a random orientation when the magnetizing field is removed accounts for what? 262. D) C) B) A) permeability coercivity retentivity nuclear magnetic resonance (NMR) The total coercive force of a magnetized piece is always 263. D) C) B) A) greater than the maximum magnetizing force less than the maximum magnetizing force equal to the saturation force determined by the residual field reduction equation The requirement for multiple switching of polarity and simultaneously reducing current amplitude is had for 264. D) C) B) A) pulsed A.C. magnetization swinging field techniques D.C. demagnetization methods surge magnetization ESTestMaker Questions 44
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In the reversing D.C. method of demagnetization the current is gradually reduced to265. D)C)B)A)the negative coercive force levelthe positive coercive force levelzeronegative saturation When a D.C. bench unit, that does not have the step down demagnetisation option built in, is used to demagnetize a part with a cable wrap, how is current reversal achieved?266. D) C) B) A) re-wrapping the coils manually switching cable connections manually switching the current selector none of the above, it cannot be used for demag purposes Field strength of a coil wrap magnetization set up can be increased by 267. D) C) B) A) reducing diameter of coil reducing current reducing turns reducing fill factor Almost anything MPI tested can be demagnetized to an acceptable level using reversing D.C. methods; but its disadvantage is 268. D) C) B) A) severe arc burns over heating of some surface finishes low production rates large equipment and dangerously high currents are used When demagnetizing a ring shaped object by passing it through a coil you would 269.
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