41. The factor responsible for the formation of discontinuous chips is
A. low cutting speed and large rake angle
B. low cutting speed and small rake angle
C. high cutting speed and large rake angle
D. high cutting speed and small rake angle
42. The stroke of a shaping machine is 250 mm. It makes 30 double strokes per minute. The overall average speed of operation is
A. 3.75 m/min
B. 5 m/min
C. 7.5 m/min
D. 15 m/min
43. The actual feed in centreless grinders is given by (where d = Dia. of regulating wheel, n = Revolutions per minute, and α = Angle of inclination of wheel)
A. πd
B. πd n
C. πd n sin α
D. πd n cos α
44. For fast removal of materials during grinding, a __________ grinding wheel is used.
A. coarse grained
B. fine grained
C. medium grained
45. Which of the following process is used for preparing parts having large curved surfaces and thin sections?
A. Hot machining
B. Ultra-sonic machining
C. ECM process
D. Chemical milling
46. A grinding wheel becomes glazed (i.e. cutting edge takes a glass-like appearance) due to
A. wear of bond
B. breaking of abrasive grains
C. wear of abrasive grains
D. cracks on grinding wheel
47. To grind brittle materials, a coarse grained grinding wheel is used.
A. Agree
B. Disagree
48. Gears can be cut on a shaper.
A. Agree
B. Disagree
49. The grade of grinding wheel depends upon
A. hardness of the material being ground
B. speed of wheel and work
C. condition of grinding machine
D. all of these
50. A dynamometer is a device used for the measurement of
A. chip thickness ratio
B. forces during metal cutting
C. wear of the cutting tool
D. deflection of the cutting tool