三副航海英语习题讲解Word格式.docx

1、D. the use of radar is necessary only when visibility is restricted、D527. Radar is not only to obtain _, but also to measure their distance away from you.A. brightness of objects B. color of targets C. shape of targets D. bearing of objectsD361. Which statement concerning the operation of radar in f

2、og is TURE ?A. radar ranges are less accurate in fog B. navigation buoys will always show up on radarC. a sandy beach will show up clearer on radar than a rocky cliffD. small wooden boats may not show up on radarB327. The correct method of switching off a marine radar is to turn power switch to _ po

3、sition first, then to _ position.A. off / standby B. standby / off C. standby / close D. close / standby【解析】雷达关机步骤。B606、As the radar antenna scans through _ a rotation , it can be show where the target is relative to your position .A. 60 degree B. 360 degree C. 180 degree D. 90 degree【解析】雷达天线。A345.

4、The radar control that reduces weak echoes out to a limited distance from the ship is the _A. sensitivity time control （ sea-clutter control） B. receiver gain controlC. brilliance control D. fast time constant （ differentiator ）【知识点】雷达的使用（控钮）【解析】近距离的杂波D346. The radar control that shortens all echoes

5、 on the display and reduces clutter caused by rain or snow is the _. A. sensitivity time control （sea clutter control） B. receiver gain control C. brilliance control D. fast time constant （differentiator）D372. _is on the panel of radar. INVERTER A391. What is the purpose of VRM control?A. To measure

6、 distance accurately B. To measure bearing accuratelyC. To measure range and bearing D. To adjust radar monitor【解析】活动距标圈。D557. SWEEP INT on radar panel is the abbreviation of_Asweep introduction Bsweep interest Csweep intention Dsweep intensity【解析】扫描亮度A605、When will you have to adjust gain ?A. every

7、 time you change ranges B. each watch C. every day D. every week【解析】增益：每次改变量程后需重新调整。D352. When hitting a solid object such as a ship or an airplane, the radar waves are reflected back _ they came.A. in the way B. the way C. by the way D. through the path【知识点】雷达的工作原理【解析】雷达波路径B360. Which general state

8、ment concerning radar is FALSE?A. raising the antenna height increases the radar range B. the ability of radar to detect objects is unaffected by weather conditionsC. radar bearing are less accurate than radar rangeD. radar should be checked regularly during clear weather to ensure that it is operat

9、ing properly 【解析】雷达探测物标的能力会受到天气的影响。A348. The radio waves used for radar are very short，only _ longAa few centimeters Ba few fathoms Ca few meters Da few feet【知识点】雷达技术指标（波长）【解析】航海雷达主要是3cm和10cmC336. The 10-cm radar as compared to a 3-cm radar of similar specifications will _.A. be more suitable for ri

10、ver and harbor navigationB. provide better range performance on low lying targets during good weather and calm seasC. have a wider horizontal beam width D. have more sea return during rough sea conditions【解析】1）最大作用距离：正常天气下，3cm雷达的大；雨雪天，10cm雷达的大。 2）距离分辨力和测距精度：波长短，脉冲前沿短，脉冲宽度短3cm好。3）方位分辨力和测方位精度：波长越短，波束宽

11、度越窄3cm好。4）抗杂波能力：10cm好。D337. The 3-cm radar as compared to a 10-cm radar with similar specifications will _.A. give better range performance in rain, hail, etc.B. display small targets in a mass of dense sea clutter at a greater rangeC. have less sea return in choppy rough seasD. display a more mapli

12、ke presentation for inshore navigationA364. Coral atolls, or a chain of islands at right angles to the radar beam, may show as a long line rather than as individual targets due to _.A. the effects of beam width B. limitations on range resolutionC. the pulse length of the radar D. the multiple-target

13、 resolution factor【知识点】雷达技术指标（天线波束宽度）【解析】天线水平波束宽度对方位分辨力的影响。A 237. You are using radar in which your own ship is shown at the center, and the heading flash always points to 00. If bearings are measured in relation to the flash, _ bearing are produced. A. relative B. true C. compass D. a circle appear

14、ing on the scope surrounding the light【知识点】雷达显示方式【解析】首向上显示方式B331. You have been observing your radar screen and notice that a contact on the screen has remained in the same position, relative to you, for several minutes. Your vessel is making 10 knots through the water. Which statement is TRUE?A. Th

15、e contact is dead in the waterB. The contact is on the same course and speed as your vesselC. The contact is on a reciprocal course at the same speed as your vesselD. The radar is showing false echoes and is probably defective【解析】相对运动C374. A radar contact will remain stationary on a relative motion

16、radar display only when it is _.A. on the same course as your vessel B. at the same speed as your vesselC. on the same course and speed as your vesselD. on a reciprocal course at the same speed as your vesselD363. You are underway at 5 knots and see on your radar a contact 10 miles directly astern o

17、f you. 12 minutes latter, the contact is 8 miles directly astern of you. What is the estimated speed of the contact? A. dead in the water B. 1 knot C. 10 knots D. 15 knots【解析】相对运动：d=（V2-V1）tC353. When using a radar in a unstabilized mode, fixes are determined most easily from _.A. center bearings B.

18、 tangent bearings C. ranges D. objects that are close aboard【解析】不稳定显示方式首向上，航向变，方位变。B375. A radar display in which North is always at the top of the screen is a（n） _.A. unstabilized display B. stabilized display C. composition display D. relative display【解析】北向上稳定显示方式。C376. A radar display which is or

19、iented,（标定方向） so that north is always at the top of the screen, is called a（n）_A. relative display B. composite display C. stabilized display D. unstabilized displayC392. What course should be fed into a stabilized radar picture?A. Compass course B. Gyro course C. True course D. Course made good【解析】

20、稳定显示方式：使用航向为真航向。A529. Your radar is set on a true motion display. Which of the following will NOT appear to move across the PPI scope?A. Echoes from a buoy B. Own ships markerC. Echo from a ship on the same course at the same speedD. Echo from a ship on a reciprocal course at the same speed【知识点】真运动【

21、解析】真运动模式A339. When the system determines that a collision situation exists, the target causing the alarm condition are identified on PPI by a bright T adjacent thereto.A. plan position indicator B. plane position indicatorC. policy proof of interest D. policy proof of interest【知识点】雷达显示【解析】平面位置显示器B37

22、7. A radar range to a small, charted object such as a light will provide a line of position in which form?A. Straight line B. Arc C. Parabola D. Hyperbola【知识点】雷达测距【解析】距离位置线C330. A navigator fixing a vessels position by radar _.A. should never use radar bearingsB. should only use radar bearings when

23、the range exceeds the distance to the horizonC. can use radar information from one object to fix the positionD. must use information from targets forward of beam【知识点】雷达定位【解析】雷达定位方法。B342. The common way to obtain your ships position is _.A. keeping a close watch and lookout B. taking a radar range an

24、d bearingC. observing a radar target and listening to signals D. keeping a well clear cautionC356. When using the radar for navigating_.A. The best fix is obtained by using a tangent bearing and a range.B. And using two radar ranges for a fix, the objects of the ranges should be closed to reciprocal

25、 bearings.C. And using ranges, the most rapidly changing range should be measured last.D. And crossing a radar range of one object with the visual bearing of a second object, the two objects should be 80 to 110 apart.【解析】测距定位时，距离变化快的后测。A341. In radar plotting is the abbreviation of _.A. closest poin

26、t to approach B. close point to approachC. crossing point to approach D. fog or steady rain【知识点】雷达标绘【解析】CPAC340. The closest point of approach （ CPA ） of a contact on a relative motion radar may be determined _.A. immediately when the contact is noted on radarB. only if the radar scope is watched co

27、nstantlyC. after the contact has been marked at least twiceD. by an occasional glance at the radar【解析】CPA的标绘方法：固定的时间间隔确定两个以上位置，连线即得相对运动线。A394. How does current and drift effect the relative motion, relative vector presentation?A. No effect B. Producing small errors in calculated aspectC. Producing l

28、arge errors in calculated aspect D. Produce errors in calculated CPA / TCPAB395. Does current and drift effect the CPA / TCPA calculations on a true motion display?A. Yes B. No C. Only a little bit D. Yes, very seriouslyB381. An indirect radar echo is caused by a reflection of the main lobe of the radar beam off the observers vessel. Which of the following is not a characteristic of indirect echoes?A. Their bearing is almost constant, even when the true bearing of the contact changes appreciablyB. They always appear on a bearing o