Aviation Electronics Technician 1 - Historic Naval Ships Association

4-31.4-32.4-33.When positive gradient conditionsexist in the ocean, layer depth isdefined as the depth of which ofthe following temperatures?1. Minimum temperature2. Maximum temperature3. Optimum temperature4. Relative temperatureWhich of the following cruisingmaneuvers by a submarine shouldprove most effective in causing asurface vessel to lose contact withthe submarine?1.2.3.4.Cruising in a uniformtemperature areaCruising above layer depthCruising below a thermoclineCruising in an isothermal layerA car is waiting at a crossing fora train to go by. The driver ofthe car honks the horn as the trainapproaches. After the train passesthe crossing, the engineer on thetrain blows the whistle. How willthe sound of the car horn heard bythe train engineer compare to thesound of the whistle heard by thecar driver?1.2.3.4.The horn will sound lower thanit actually is, and the whistlewill sound higher than itactually isThe horn will sound lower thanit actually is, and the whistlewill sound lower than itactually isThe horn will sound higher thanit actually is, and the whistlewill sound higher than itactually isThe horn will sound higher thanit actually is, and the whistlewill sound lower than itactually is4-34. As a sound emitter moves away froma receiver, which of the followingapparent changes will occur?1.2.3.4.Only frequency will increaseOnly wavelength will increaseWavelength and frequency willincreaseWavelength will decrease4-35. Which of the following sounds arerarely heard by the sonar operator?1. Pings2. Target echoes only3. Reverberations only4. Reverberations and targetechoesIN ANSWERING QUESTIONS 4-36 THROUGH 4-39,SELECT FORM COLUMN B THE RELATIVE PITCH OFTHE REFLECTED SOUND THAT IS MOSTDESCRIPTIVE OF EACH OF THE MOTIONCONDITIONS LISTED IN COLUMN A. NOT ALLRESPONSES IN COLUMN B ARE USED.4-36.4-37.4-38.4-39.A. RELATIVEMOTIONSSonar stationary,all signalsreceived classedas reverberationechoesSonar and targetmoving in oppositedirections, andseparatingSonar and targetmoving towardeach otherSonar and targetmoving abreast andthe same directionB. RELATIVEPITCH1. Higher2. Lower3. Same4. Undulatingin26