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This section includes 335 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
251. |
When a longitudinal wave is incident upon an inclined interface between zero degrees and the first critical angle: |
A. | The sound beam is totally reflected |
B. | Only shear waves are produced in the second material |
C. | Shear waves and longitudinal waves are produced in the second material |
D. | Only longitudinal waves are produced in the second material |
Answer» D. Only longitudinal waves are produced in the second material | |
252. |
Where possible, circular magnetisation is preferable to longitudinal magnetization because: |
A. | Less current is required |
B. | Stronger fields are obtained |
C. | Fewer confusing secondary poles are produced |
D. | None of the above is true |
Answer» E. | |
253. |
On the area-amplitude ultrasonic standard test blocks, the flat-bottomed holes in the blocks are: |
A. | All of the same diameter |
B. | Different in diameter, increasing by 1/64 inch increments from the No. 1 block to the No. 8 block |
C. | Largest in the No. 1 block and smallest in the No. 8 block |
D. | Drilled to different depths from the front surface of the test block |
Answer» C. Largest in the No. 1 block and smallest in the No. 8 block | |
254. |
A leakage field is strongest when a discontinuity interrupts the magnetic flux lines at an angle of: |
A. | 0o |
B. | 45o |
C. | 90o |
D. | 180o |
Answer» D. 180o | |
255. |
Highest sensitivity to fine surface cracks would be obtained by which of the following techniques? |
A. | Residual field, wet method |
B. | Residual field, dry method |
C. | Continuous field, wet method |
D. | Continuous field, dry method |
Answer» D. Continuous field, dry method | |
256. |
Which of the following methods might be used to reduce attenuation losses in an ultrasonic test? |
A. | Use a shorter wavelength |
B. | Use a lower frequency transducer |
C. | Change from longitudinal waves to shear waves |
D. | Change to a coarser grained test piece |
Answer» C. Change from longitudinal waves to shear waves | |
257. |
An ultrasonic display which shows a cross section of the test piece and any flaws which are found are called: |
A. | A scan |
B. | B scan |
C. | C scan |
D. | Orthogonal view |
Answer» C. C scan | |
258. |
The fact that gases, when bombarded by radiation, ionise and become electrical conductors make them useful in: |
A. | X ray transformers |
B. | X ray tubes |
C. | Masks |
D. | Radiation detection equipment |
Answer» E. | |
259. |
When conducting an immersion test, the water path distance must be controlled so that: |
A. | Spurious signals are not created by surface waves on the test piece |
B. | The (water path distance)/(diameter) ratio does not result in asymmetric standing waves |
C. | The test piece discontinuity indications appear between the first front and first back surface echos |
D. | The second front surface echo does not appear on the CRT screen between the first front and first back surface echos |
Answer» D. The second front surface echo does not appear on the CRT screen between the first front and first back surface echos | |
260. |
The angle formed by an ultrasonic wave as it enters a medium of different velocity than the one from which it came and a line drawn perpendicular to the interface between the two media is called: |
A. | The angle of incidence |
B. | The angle of refraction |
C. | The angle of diffraction |
D. | The angle of reflection |
Answer» C. The angle of diffraction | |
261. |
The formula, NI = 45000/(L/D), gives proper magnetising current for a coil, regardless of coil size as long as: |
A. | The test piece is not larger than 1/10 the cross sectional area of the coil |
B. | AC current only is used |
C. | The test piece essentially fills the coil |
D. | The test piece is held tightly against the coil |
Answer» B. AC current only is used | |
262. |
A technique used to find transverse discontinuities at the ends of longitudinally magnetised bars by the use of transient currents is called: |
A. | A coil technique |
B. | A fast break technique |
C. | A yoke technique |
D. | A head shot |
Answer» C. A yoke technique | |
263. |
What rule describes the direction of current flow (+ to -) when lines of magnetic force surround a conductor? |
A. | Left hand rule |
B. | Right hand rule |
C. | Flux density rule |
D. | Reluctance rule |
Answer» C. Flux density rule | |
264. |
The field in a section of pipe being magnetised by means of a central conductor is stronger at: |
A. | The ends of the pipe |
B. | The outer surface of the pipe |
C. | The inside surface of the pipe |
D. | The middle of the pipe wall |
Answer» D. The middle of the pipe wall | |
265. |
When contouring an angle beam wedge for a convex surface, an undesirable result of a wedge which is contoured too well might be: |
A. | Production of unwanted surface waves |
B. | Greater beam divergence due to larger contact area |
C. | Lower beam divergence due to larger contact area |
D. | Overly efficient coupling of sound beam into test part |
Answer» B. Greater beam divergence due to larger contact area | |
266. |
When a magnetic field is induced in a part with prods spaced 150mm apart, the field is: |
A. | Solenoidal |
B. | Circular |
C. | Longitudinal |
D. | Distorted trapezoidal |
Answer» C. Longitudinal | |
267. |
The most important factor required for the proper interpretation of ultrasonic test results is: |
A. | The ultrasonic signal amplitude |
B. | A knowledge of the test specimen material and its construction |
C. | A knowledge of the ultrasonic instruments operating characteristics |
D. | The ultrasonic signal location |
Answer» C. A knowledge of the ultrasonic instruments operating characteristics | |
268. |
The film processing step in which the undeveloped silver bromide is removed from the film emulsion is called: |
A. | Development |
B. | Stop bath |
C. | Fixing |
D. | Rinsing |
Answer» B. Stop bath | |
269. |
A continuous linear indication along the edge of a new fillet weld would most likely be a: |
A. | Crater crack |
B. | Fatigue crack |
C. | Stress corrosion crack |
D. | Heat affected zone hydrogen crack |
Answer» E. | |
270. |
The process of loading more than one film into a cassette is known as the technique: |
A. | Single film technique |
B. | Multiple film technique |
C. | none |
D. | none |
Answer» C. none | |
271. |
With current flowing from + to - in a coil, a longitudinal field is created. Which of the following may be used to establish the direction of the magnetic field? |
A. | Left hand rule |
B. | Right hand rule |
C. | Ohms law |
D. | There is no relevant law |
Answer» C. Ohms law | |
272. |
The flux within and surrounding a magnetised part or around a conductor carrying a current is known as: |
A. | Saturation point |
B. | Magnetic field |
C. | Ferromagnetic |
D. | Paramagnetic |
Answer» C. Ferromagnetic | |
273. |
Why should one avoid using a high velocity flow of a wet testing media over the test area |
A. | It may wash away a fine or lightly held indication |
B. | This is not a problem |
C. | It may splash particle into eyes |
D. | None of the above are correct |
Answer» B. This is not a problem | |
274. |
In which magnetizing method is the current passed directly through the part, thereby setting up a magnetic field at right angles to the current flow? |
A. | Longitudinal magnetization |
B. | Coil magnetization |
C. | Central conductor magnetization |
D. | None of the above |
Answer» E. | |
275. |
According to ASMT E709-95 alternating current electromagnetic yokes should give a lifting force of at least: |
A. | 1.5 kg |
B. | 2.5 kg |
C. | 3.5 kg |
D. | 4.5 kg |
Answer» E. | |
276. |
The space within and surrounding a magnetized part of a conductor carrying a current is known as: |
A. | Saturation point |
B. | Magnetic field |
C. | Ferromagnetic |
D. | Paramagnetic |
Answer» C. Ferromagnetic | |
277. |
Compared to the magnetic field strength at the outer surface, the magnetic field strength, at the centre of a hollow, nonmagnetic conductor carrying DC current is: |
A. | I/D |
B. | The same |
C. | Zero |
D. | Need more information to determine |
Answer» D. Need more information to determine | |
278. |
Subjecting the part to a magnetic field that is constantly reversing in polarity and gradually diminishing in strength accomplishes which of the following: |
A. | Magnetises the part |
B. | Removes residual field from the part |
C. | Soaks in the flux density |
D. | Helps find deep lying defects |
Answer» C. Soaks in the flux density | |
279. |
According to ASTM E709-95, Table 3., direct current electromagnetic yokes must have a lifting force of at least: |
A. | 15 kg (33 lb) |
B. | 16 kg (36 lb) |
C. | 17 kg (38 lb) |
D. | 18 kg (40 lb) |
Answer» E. | |
280. |
The primary reason for using water rather than oil as a suspension medium for wet method baths is that |
A. | Water is more chemically inert than oil |
B. | Bath flammability hazards are eliminated |
C. | Water has the capability to dissolve the needed rust inhibitors |
D. | Water baths may be used at a lower temperature than oil baths |
Answer» C. Water has the capability to dissolve the needed rust inhibitors | |
281. |
The magnetic particles are noticed to bunch in some fillet areas and stand on end on the edge of a part being magnetized. These observations indicate that the: |
A. | Particle concentration is too low |
B. | Flux density is excessive |
C. | Flux density is too low |
D. | Magnetizing current should be changed form AC to DC |
Answer» C. Flux density is too low | |
282. |
When using the wet continuous method, the flow of suspension from the hose should be shut off: |
A. | Immediately after applying the current |
B. | Immediately before applying the current |
C. | While the current is flowing |
D. | Thirty seconds before applying the current |
Answer» D. Thirty seconds before applying the current | |
283. |
Which of the following describes the best technique for applying dry magnetic particles to a test piece? |
A. | Dip the test piece in a tank of dry particles while current is flowing |
B. | Apply with an electrostatic spray gun at approximately 30 PSIG |
C. | Gently pour the powder onto the test piece |
D. | Shake or dust the powder onto the test piece with minimum velocity |
Answer» E. | |
284. |
According to AST M E709-95 and API, after removing magnetization of parts after examination, the residual magnetism shall not exceed (1 gauss = 0.0001 tesla): |
A. | 3 10-4T (3gauss) |
B. | 4 10-4T (4 gauss) |
C. | 6 10-4T (6gauss) |
D. | 8 10-4T (8 gauss) |
Answer» B. 4 10-4T (4 gauss) | |
285. |
To provide reliability and reproducibility in magnetic particle testing, written procedures should include: |
A. | Location of the coil and current for each magnetization |
B. | Requirements for ammeter calibration |
C. | Type and concentration of the particles |
D. | All of the above |
Answer» E. | |
286. |
Which of the following types of intensifying screens are not used in industrial radiography? |
A. | Lead |
B. | Fluorescent |
C. | Silver halide |
D. | All of the above |
Answer» D. All of the above | |
287. |
According to ASTM E709-95, with wet continuous magnetization technique, the duration of magnetization current is of the order of: |
A. | 0.5 sec |
B. | 1.0 sec |
C. | 1.5 sec |
D. | 2.0 sec |
Answer» B. 1.0 sec | |
288. |
The important difference between AC and DC current for magnetic particle testing purposes is: |
A. | The skin effect caused by DC adds mobility to the magnetic particles |
B. | The resulting AC magnetic fields are more difficult to demagnetize |
C. | The DC magnetic fields are more penetrating |
D. | The AC magnetic fields are stronger |
Answer» D. The AC magnetic fields are stronger | |
289. |
Gamma ray or high voltage X ray radiography, using film without lead screens, is likely to result in: |
A. | Mottling of the film |
B. | Increased geometric unsharpness |
C. | No apparent difference, but increased exposure time |
D. | No apparent difference, but decreased exposure time |
Answer» B. Increased geometric unsharpness | |
290. |
According to ASTM E709-95 with prod technique, the prods shall be tipped if the open circuit voltage is over: |
A. | 10 V |
B. | 15 V |
C. | 20 V |
D. | 25 V |
Answer» E. | |
291. |
For detection of longitudinal discontinuities a 7.6 cm (3 inches) diameter bar is magnetized in: |
A. | The longitudinal direction |
B. | The circular direction |
C. | The clockwise direction |
D. | None of the above directions |
Answer» C. The clockwise direction | |
292. |
Which of the following techniques would probably reduce the amount of scattered radiation reaching the film during a radiographic exposure? |
A. | Using a finer grained film |
B. | Using a filtered X ray beam |
C. | Removing lead screens |
D. | All of the above |
Answer» C. Removing lead screens | |
293. |
If the required exposure time for a 50 Curie Ir-192 source is 4 minutes, what exposure time would be required at 25 Curie source: |
A. | 4 minutes |
B. | 8 minutes |
C. | 2 minutes |
D. | 16 minutes |
Answer» C. 2 minutes | |
294. |
If it were necessary to radiograph 18 cm (7 in.) thick steel product, which of the following gamma ray sources would most be used? |
A. | Cs 137 |
B. | Tm 170 |
C. | Ir 192 |
D. | Co 60 |
Answer» E. | |
295. |
In order to increase latitude so that thick and thin portions may be radiographed at reasonable viewing densities simultaneously: |
A. | Fluorescent screen should be employed |
B. | Led screens should be at least 5 mm thick |
C. | The cassette may be loaded with two separate films of different speeds |
D. | Radiograph the object at low energy |
Answer» D. Radiograph the object at low energy | |
296. |
Which of the following is NOT a liquid vehicle in which particles are suspended in magnetic particle testing: |
A. | Water treated with a wetting agent |
B. | Kerosene |
C. | Gasoline |
D. | Water treated with antifoam |
Answer» D. Water treated with antifoam | |
297. |
Which type of gamma ray source would be used to radiograph a weld in 150 mm thick steel plate? |
A. | Ir-192 |
B. | Co-60 |
C. | Tm-170 |
D. | Cs-137 |
Answer» C. Tm-170 | |
298. |
An exposed radiographic film which transmits 1% of the light incident on it has what density: |
A. | 1.0 |
B. | 2.0 |
C. | 99.0 |
D. | 0.5 |
Answer» D. 0.5 | |
299. |
When using a radioactive isotope in making a radiograph, we can express the equation for exposure as Ci T. In this equation , Ci stands for: |
A. | Current through tube |
B. | Intensity in curies or becquerels |
C. | Degree of contrast |
D. | Coarseness of the film |
Answer» C. Degree of contrast | |
300. |
According to ASTM E709-95 when dry particles are used magnetic particle testing shall not be performed on the surface of parts whose temperature exceeds: |
A. | 57 C |
B. | 79 C |
C. | 158 C |
D. | 136 C |
Answer» B. 79 C | |