RT I级基础理论试题.doc

RT I级基础理论试题 RT Level I General Examination 姓名：_______________得分：______________ 主考官：________________ Name Score Examiner 如果在36”焦距的情况下得到一张好的底片，那么当焦距变为18”而其他条件均不变的情况下，曝光时间将会： An excellent radiograph is obtained under given conditions of exposure with the film located at a distance of 36 inches from the target of the X-ray tube. If the film is now placed only 18 inches from the target, and all exposure conditions except time are held constant, the new exposure time will be: 不变 unchanged 增加大约80% longer by approximately 80 percent 缩短大约55% shorter by approximately 55 percent 只是原时间的大约1/4 only about 25 percent as long as the original exposure time RT时，透度计通常放于： In film radiography, penetrameters are usually placed: 增感屏和胶片之间 between the intensifying screen and the film 摆在被测工件的源侧 on the source side of the test object 被测工件的胶片侧 on the film side of the test object 在操作者和源之间 between the operator and the radiation source 当底片要求2-T质量等级时，对0.5”的铝合金其所用的ASTM透度计的厚度为：（1 mil = 1/1000英寸） When radiographing to the 2-2T quality level, an ASTM penetrameter for 1/2-inch thick 2024 aluminum alloy has a thickness of: 0.5” 2 mils 5 mils 10 mils X射线的穿透力由_____控制： The penetrating ability of an X-ray beam is governed by: 电压或波长 kilovoltage or wavelength 时间 time 毫安值 milliamperage 源—胶片距离 source-to-film distance 用于NDT的Co 60发射： Cobalt-60 used in nondestructive testing emits: ?粒子 alpha particles 中子 neutrons r射线 gamma rays X射线 X rays 黑度计是： A densitometer is: 测量X射线强度的尺子 a meter used to measure X-ray intensity 测底片黑度的仪器 an instrument for measuring film density 测材料密度的量具 a meter used to measure the density of a material 测管电流的量尺 a meter used to measure tube current 暗室处理的三种基本液体是： Three liquids which are essential to process an exposed film properly are: 停影液、醋酸、水 stop bath, acetic acid, and water 显影液、停影液、双氧水 developer, stop bath, and H2O2 显影液、定影液、水 developer, fixer, and water 醋酸、定影液、停影液 acetic acid, fixer, and stop bath 使底片黑度直线上升的二个最常见原因是： The two most common causes for excessi