amE)       S = m/a 77)      Horzontal slicing method is applied if the seam thickness isA)       less than 5mB)       more than 15mC)       more than 10mD)       less than 15 mE)       less than 10m 78)      Given the following            Minng method                                                             Technique           P. Thick seam extraction                                     1.Double unit face           Q. Bord and pillar extraction                                2.Jet cutting           R. Longwall face development                             3.Inclined slicing           S. Hydraulic mining                                             4.Half moon methodA)       P-3, Q-4, R-1, S-2B)       P-3, Q-4, R-2, S-1C)       P-1, Q-4, R-2, S-3D)       P-3, Q-2, R-1, S-4E)       None of the above 79)      Ward - Leonard system is provided in the winding system in order to restrictA)       Over speeding of cageB)       Acceleration of the cageC)       Over winding of the cageD)       Deceleration of the cageE)       none of the above 80)      If there are more than one rock type, then the combined RMR is obtained as –A)       Σ(RMR of each bed + bed thickness) / Σ(thickness of each bed)B)       None of theseC)       Σ(Compressive strength of each bed X bed thickness) / Σ( Compressive strength of each bed)D)       Σ( Compressive strength of each bed + bed thickness) / Σ(thickness of each bed)E)       Σ(RMR of each bed X bed thickness) / Σ(thickness of each bed) 81)      Of the given options which type of rock is best suited for rotary drills?A)       Weak rocks and abrasive rocksB)       Highly abrasive and low strength rocksC)       Medium strength and non-abrasive rocksD)       Very Strong and abrasive rocksE)       Medium strength and abrasive rocks 82)      If the spoil bank exceeding          metre in height shall be benched so that no bench exceeds    metre in height and the overall slope shall not exceed 1 vertical to 1.5 horizontal.A)       30 m, 30mB)       60m, 30mC)       30m, 15 mD)       45 m, 15mE)       45m, 30m 83)      A bord of 3 m height and 3.5 m width is being developed in an underground coal mine. 15 nos. of 1.8 m long 38 mm dia. blasthole with an average charge of 350 gm/hole is used per blasting round. The average pull is 1.5 m. If the in-situ density of coal is 1.67 tonne/m3, the powder factor is nearly equal to   .A)       6 tonne /kg of explosiveB)       3 tonne /kg of explosiveC)       4 tonne /kg of explosiveD)       2 tonne /kg of explosiveE)       5 tonne /kg of explosive 84)      Match the following in the context of environmental management.            Technique                                                       Purpose           P.Mulching                                                         1.Dust control           Q.Aeration                                                          2.Noise control           R.Wet-scrubbing                                                 3.Soil conservation           S.Silencer                                                           4.Waste water treatmentA)       P-3, Q-1, R-4, S-2B)       P-4, Q-3, R-1, S-2C)       P-3, Q-4, R-1, S-2D)       None of the aboveE)       P-1, Q-4, R-3, S-2 85)      A mining method should be developed and designed to economically mine a deposit of ore/mineral/fossil fuel taking care of       ,           and  fulfilling production demand and statutory requirements.A)       production; productivity; conservationB)       safety; production; productivityC)       conservation; safety; environmentD)       safety; conservation; productivityE)       safety; environment; production  86)      In a blasting round for drivage of a 3.2 m × 3.0 m cross-cut 20 nos. of 1.8 m long holes are used. If the average pull is 1.5 m and the in-situ density of rock is 2.78 tonne/m3, the yield per detonator will be approximately     .A)       1.8 tonneB)       2.2 tonneC)       1.6 tonneD)       2.0 tonneE)       2.4 tonne 87)      In case of full height development of a coal seam, formation of square pillar of 42 m x 42 m (centre to centre) with 3.6 m wide gallery will cause  .A)       22.6% of coal extraction during pillar formation.B)       30.5% of coal extraction during pillar formation.C)       None of the aboveD)       16.4% of coal extraction during pillar formation.E)       25% 88)      The immediate roof of a mine is supported by bolts of length 1.5 m, arranged in 1.2 m x 1.2 m grid pattern. If the unit weight of roof rock is 2.25 tonne/cu.m. and load carrying capacity of each bolt is 7.5 tonne, the factor of safety of the support system is.....A)       3.0 to 3.1B)       2.0 to 2.1C)       None of the aboveD)       1.4 to 1.6E)       3.8 to 4.0 89)      Bench failure is caused byA)       linear tensionB)       all of theseC)       two tensions in inclined directionsD)       multi-directional tensionsE)       over-loading 90)      Which of the following is not a general mode of slope failure?A)       Shear failureB)       Rotational failureC)       Planar failureD)       Toppling failureE)       None of the Options 91)      RMR of immediate roof in an underground mine 55. For 3 m wide gallery the rock load will be approximately …... Given, roof rock density 2.5 t/m3.A)       3.5 t/m2B)       2.0 t/m2C)       3.0 t/m2D)       1.5 t/m2E)       2.5 t/m2 92)      Support system design based on RMR depends on the following   .A)       width of galleryB)       method of excavationC)       Depth of seamD)       Roof rock load densityE)       All of the above 93)      If the bench height is 10m, burden 4 m, specing 5m, sub-grade drilling 1m, explosive per hole 110 kg, density of rock 2500 kg/m3, then powder factor will beA)       6.5B)       5.5C)       5D)       6E)       4.5 94)      If the bench height is 10m, burden 4 m, specing 5m, sub-grade drilling 1m, explosive per hole 110 kg, density of rock 2500 kg/m3, then detonator factor will beA)       600B)       500C)       450D)       400E)       550 95)      At the nozzle in hydraulic mining operation, what should be the minimum pressure to be maintainedA)       5-10 kgf/       15-20 kgf/       40-100 kgf/       21-35 kgf/       10-20 kgf/ 96)      Where two or more contiguous seam are worked in a mine, the pillars in one seam shall, as far as practicable, be vertically above or below the pillars in the other seam unless the strata are inclined at an angle of more than            degrees from the horizontal.A)       15B)       30C)       45D)       25E)       20 97)      Match the following location with support types in coal mines -            Location                                              Support type           P.Roadway junctions                              1.Powered support           Q.Between adjacent panels                     2.Chock and bolt           R.Longwall face                                      3.Back fill           S.Goaf                                                   4.Barrier pillarA)       P-4, Q-3, R-1, S-2B)       P-2, Q-3, R-4, S-1C)       None of the aboveD)       P-2, Q-3, R-1, S-4E)       P-2, Q-4, R-1, S-3 98)      A 15 cum dragline works for 30 days @ 6 hrs per shift and 3 shifts a day. The cycle time , bucket fill factor and operating efficiency are 50 s, 0.85 and 75 % respectively. What will be the total volume in cum handled by the dragline in a month ?A)       351720 cumB)       45750 cumC)       371790 cumD)       427860 cumE)       349970 cum 99)      Given the following            Machine                                               Component           P. Dint header                                        1.Cowl           Q. Coal plough                                        2.Cutting chain           R. Road header                                      3.Loading apron           S. Shearer                                              4.Static set of bitsA)       P-3, Q-4, R-2, S-1B)       P-2, Q-4, R-3, S-1C)       None of the aboveD)       P-2, Q-3, R-4, S-1E)       P-4, Q-2, R-3, S-1  100)    Min. std. of horizontal and vertical illumination in Lux at places where manual work is done in opencast coal mine are---respectively. A)       15H, 15V B)       15H, 25V C)       15H,10V D)       10H, 5V E)       10H, 10  CLICK ME TO DOWNLOAD Question Paper & Key of FIRST CLASS UNRESTRICTED UNDER CMR-WINNING AND WORKING EXAM 2021" /> FCU-WINNING & WORKING DGMS EXAM-2021 | Mine Portal - India's No.1 Mining Exams Test Series Provider