QUIZ) ASNT L3 BASIC 14

261. which of the following is not a property of magnetic lines of force?

a. they form closed loops which do not cross

b. the density increases with increasing distance from the poles of a permanent magnet

c. they are considered to have direction

d. they seek paths of least magnets resistance of least reluctance

262. surrounding an electromagnet the magnets field is strongest

a. immediately after the current ceases to flow

b. while the magnetizing current is flowing

c. at the time the magnetic particles are applied to the part

d. must prior to current reversal

263. how many turns of a coil will be needed to establish a longitudinal field in a steel shaft that is 9 inches long

with 3 inches diameter? 3000 amperes magnetizing current is available it is desired to magnetize the part in

accordance with the formula N = (45000/ L/D)

a. 1 b. 3 c. 5 d. 7

264. how many ampere-turns are required to magnetize a part that is 16 inches long and 2 inches in diameter?

a. 9000 ampere-turns

b. 5625 ampere-turns

c. 2812 ampere-turns

d. 40 ampere- turns

265. what is the recommended amperage range per inch of diameter generally used for circular magnetization of

parts using a DC source?

a. 500 - 700

b. 800 - 1000

c. 1200 - 1400

d. maximum available to insure total magnetization

266. the lines of flux or force in a circularly magnetized ferromagnetic bar

a. are aligned through the piece from the south to the north pole

b. are aligned through the piece from the north to the south pole

c. leave the south pole and enter the north pole

d. are contained within and around the part

267. the field in a section of ferromagnetic pipe being magnetized by means of a central conductor is strongest

at the

a. ends of the pipe

b. outer surface of the pipe

c. inside surface of the pipe

d. middle of the pipe wall

268. A cylindrical part is to be tested using circular magnetization. The part has three different diameters

along its length. A rule of thumb for current values for each diameter provides three current levels. Which

of the derived current values should be applied first?

a. The highest value

b. The median value

c. The lowest value

d. It does not matter which is applied first

269. which of the following is the type of magnetic field that can be induced in parts using permanent magnet

yoke?

a. circular b. vector c. direct d. longitudinal

270. an advantage of magnetic rubber is that

a. it can be used on non-ferromagnetic materials

b. it can be stripped off the surface and examined using magnification

c. it is a very rapid test method

d. the materials used are less expensive than dry powder

271. a critical problem was found where fatigue cracks were initiating from the roots of a threaded hole. Which

of the following should be used if available?

a. magnetic rubber and DC magnetic yoke

b. filling the hole with a wet suspension and using a borescope

c. X-ray

d. eddy current boll hole probe

272. which of the following is the most effective method for the detection of extremely deep-lying defects?

a. dry residual method using DC with surge

b. wet continuous method using half wave rectified current

c. wet residual method

d. dry continuous method using half wave rectified current with prods

273. the point at which the magnetism in a material cannot be increased even though the magnetizing force

continues to increase is known as the

a. salient pole

b. saturation point

c. residual point

d. remnant point

274. if an overall pattern (sometimes circular lines) appears on the test surfaces how should the inspector

reprocess the test piece?

a. retest at a higher amperage

b. demagnetize

c. retest at lower amperage

275. a material support for holding core in place during casting which fails to metals produce a discontinuity

a. non-metallic inclusion

b. cold shut

c. unfused chill

d. unfused chaplet

276. an important application of NDT such as ultrasonic and eddy current testing to thin sheet metals is in

a. material sorting

b. proof testing

c. thickness measurement

277. which of the following tests would indicate whether a stainless steel part is a 400 series or a 300 series

stainless steel?

a. specific gravity

b. hardness

c. magnetic attraction

d. tensile strength

278 the testing for fatigue cracks ~~~ from fastener hole in air craft?

a. Gamma radiography availed to the fastener axis

b. early current pancake coil covering the fastener hole surface

c. ultrasonic longitudinal wave(straight beam) parallel to the fastener axis

d. vacuum leak testing avail the surface of the fastener hole

279. very short wavelength electromagnetic radiation produced when electrons traveling at high speeds collide

with matter is called

a. x-radiation b. beta radiation c. gamma radiation

280. materials exposed to gamma radiation or to million volt x-rays

a. should not be handled for at least 3 minutes after exposure has ceased

b. should be stored in a lead-lined room

c. will not be dangerous to handle after exposure to radiation has ceased

d. should be monitored by means of a geiger counter

 

 

 

 

 

 

 

 

 

ANSWER

 

 

261	262	263	264	265	266	267	268	269	270
B	B	C	B	B	D	C	C	D	B
271	272	273	274	275	276	277	278	279	280
A	D	B	C	D	C	C	B	A	C