This set of Engineering Metrology Multiple Choice Questions & Answers (MCQs) focuses on “Visual Inspection”.
1. What is the use of an interference microscope?
a) Measure depth of scratches
b) Measure width of crack
c) Develop a permanent visual record
d) Only illuminate the cracks
Explanation: Interference microscope is used to measure the depth of scratches in the finish of finely lapped or polished surfaces. This is a nondestructive technique and is generally used in visual inspection.
2. What is the tube diameter of rigid borescope?
a) 0.1 to 10 mm
b) 0.5 to 90 mm
c) 0.2 to 100 mm
d) 0.9 to 70 mm
Explanation: The borescope’s applications are limited with a straight line path between the observer and surface to be observed. The diameter of tube of rigid borescope may range from 0.9 to 70 mm and length from 0.15 to 30 metres.
3. What is the use of fluorescent penetrants?
a) Develop permanent visual records of a remote object
b) Illuminates and observes internal, closed or inaccessible areas
c) Enhance the observation of surface cracks
d) Evaluate surface finish, shape and microstructure
Explanation: Fluorescent penetrants are generally used for visual inspection. It is used to enhance the observation of cracks. Image sensors are also used for visual inspection which develops permanent visual records.
4. What is the field of view range of borescope?
a) 30 to 180 degree
b) 10 to 90 degree
c) 60 to 360 degree
d) 10 to 180 degree
Explanation: The field of view of borescope can range from 10 to 90°. It is possible to have orbital scan which involves the rotation of the optical shaft for scanning purpose. The illumination system used in bprescope incorporates features like different viewing head, orbital scan, and adjustable focussing of the objective lens.
5. What type of fibre is present in the optical tube of mini borescope?
a) Quartz fibre
b) Asbestos fibre
c) Plastic fibre
d) Resin fibre
Explanation: Mini borescope uses a single image-relaying rod or quartz fibre in the optical tube in place of conventional relay lenses. Mini borescope is a variant of borescope along with hybrid borescopes, extendable borescopes, or rigid chamberscope.
6. Which of the following option is true about hybrid borescopes?
a) Use rod lenses combined with concave lenses
b) Use rod lenses combined with concave mirror
c) Use rod lenses combined with convex lenses
d) Use rod lenses combined with convex mirror
Explanation: Hybrid borescopes uses rod lenses combined with convex lenses to-relay the image. Extendable borescope enable the use of extension tubes. These both are the variants of the borescope and used for visual inspection.
7. Upto which length the flexible fiberscopes are available?
a) 12 m
b) 14 m
c) 16 m
d) 18 m
Explanation: Flexible fiberscopes are available upto 12 m length and in diameter range of 1.4 to 13 mm. Image guide fibres with fibre size 65 to 17 µm and light guide bundle with 30µm diameter fibre are used in flexible fiberscopes.
8. Which of the following option is true for the given statements about flexible fibrescope?
Statement 1: Fibrescope produce higher resolution than videoscope.
Statement 2: Videoscopes have longer working length than fibrescope.
a) T, T
b) T, F
c) F, F
d) F, T
Explanation: Videoscopes produce higher resolution and have longer working length than fiberscope. The display used in this reduces eye fatigue and enables point-to-point measurement on the viewing screen with the help of reticles.
9. For what distance, videoscopes are used with CCD probes for electronic transmission?
a) Less than 15 m
b) More than 15 m
c) Less than 10 m
d) More than 10 m
Explanation: For more than 15 meter distance, videoscopes with CCD probes or charge coupled device probes are used for electronic transmission of black and white or colour images to a video monitor.
10. Which of the following is not true about rigid chamberscope?
a) Enable use of extension tube
b) Have zoom facility
c) Used for rapid inspection
d) Offer greater magnification
Explanation: Chamberscopes offer more magnification than conventional rigid borescopes. They have zoom facility and used for rapid inspection of large chambers. They include variable direction of view with high intensity lightning.
11. Where does the CCD chip is placed in flexible fiberscope?
a) At proximal end
b) Ar median point
c) At the distal end
d) Anywhere between proximal and distal end
Explanation: A CCD chip consists of a large number of light-sensitive picture elements or pixels arranged in a pattern of rows and columns, is placed at the distal end. The objective lens focuses the object image on the surface of the CCD chip.
12. Which type of special purpose system is used for the examination of hazardous process or for extreme radiations?
d) Vacuum borescope
Explanation: Periscopes allow examination of dangerous or hazardous areas. Periscopes are designed for high pressure and temperature, extreme radiation or underwater applications. Vacuum borescopes recording and observation of images inside vacuum chambers.
13. Which of the following is not true for rigid borescopes?
a) Operates like telescope in reverse
b) Good for rapid examination
c) Video adaptation is present
d) Semi Rigid sheathing is present
Explanation: Semi rigid borescopes are operated like telescope in reverse. A borescope spreads the field of view. Semi Rigid sheathing is present in flexible illuminated fibrescopes and it allows the inspection at most difficult to reach spots.
Sanfoundry Global Education & Learning Series – Engineering Metrology.
To practice all areas of Engineering Metrology, here is complete set of 1000+ Multiple Choice Questions and Answers.