Details

1)        Every shaft, incline and other outlets provided in an underground coal mine shall be examined, once at least in every……, by an ……. or other competent person and a report of every such examination shall immediately thereafter be recorded in a bound paged book kept for the purpose and shall be signed and dated by the person making the examination.

A)       Fifteen Days; Overman

B)       Seven Days; Overman

C)       Four Weeks; Overman

D)       Seven days; Mining Sardar

E)       Fifteen Days; Mining Sardar

2)        A mine is being developed by bord and pillar method with a gallery size of 4.8 m x 2.4 m. The mine operates in 3 shift per day and 6 faces are blasted per shift. The average pull per round of blast is 1.2 m and the bulk density of the coal is 1.4 tonne/cu.m.. If the OMS is 2.5, then the average manpower deployed in the development section per shift is ----

A)       46 to 47

B)       52 to 53

C)       55 to 56

D)       None of the above

E)       49 to 51

3)        In a drum hoisting system through a vertical shaft, overwinding is prevented by

A)       safety catch

B)       Lilly controller

C)       detaching hook

D)       None of the above

E)       caliper brake

4)        In case of manual opencast mine where any pillar is left ‘in situ’ for the purpose of measurement, its height shall ……. and where the height of such pillar exceeds 1.25 meters, the base of the pillar shall not be less than …….. meters in diameter.

A)       not exceeds 2.25 meters, 2.0

B)       not exceed 3.5 meters; 3.0

C)       None of the above.

D)       not exceed 4.5 meters; 3.5

E)       not exceed 2.5 meters; 1.5

5)        Which of the following appliance is used to give suitable curvature to a track line

A)       jim screw

B)       backstay

C)       monkey catch

D)       run away switch

E)       drop war wick

6)        When two working places belowground have approached within  meters of each other, the shot- firer shall not fire any shot in any one of the said workings unless all persons have been withdrawn from the other working place and the same has been so fenced off as to prevent persons inadvertently coming in direct line of the shot.

A)       4.5; stone dusted

B)       9; fenced off

C)       None of the above.

D)       7.5; posting of guard

E)       6; sprayed with water

7)        Air borne dust survey shall be done

A)       At least in a quarter

B)       At least once in a year

C)       At least once in every month

D)       None of these

E)       At least once in every six month

8)        The specimen obtained from the field were tested in uniaxial compression and the following results were obtained at 50% of an average compressive strength. Longitudinal strain = 7x10-2 Lateral strain = 1.4 x 10-2. Find the ratio of vertical to horizontal stress inthe mine.

A)       3.06

B)       none of the above

C)       4.00

D)       3.50

E)       3.00

9)        In this equation σt represents the of rock.

A)       RMR

B)       Compressive Strength

C)       Tensil Strength

D)       RQD

E)       Shear Strength

10)      A coal heading 4 m wide and 2.5 m wide has an advance of 1.0 m per cycle. The amount of explosive used in blasting is 6 kg. Taking specific gravity of coal as 1.5, the power factor is             

A)       3.32 te/kg

B)       2.99 te/kg

C)       none of the above

D)       2.50 te/kg

E)       1.66 te/kg

11)      Cavability of sandstone roof does not depend on  .

A)       density of coal

B)       compressive strength

C)       average length of core

D)       thickness of strong bed

E)       presence of joint planes in roof rock

12)      Coal seams having Energy Index above______are highly prone to coal bumps.

A)       3

B)       5

C)       11

D)       7

E)       9

13)      The roadways in an underground coal mine developed___________to the major horizontal stress would experience maximum stress concentration.

A)       reverse

B)       diagonal

C)       opposite

D)       parallel

E)       normal

14)      Purpose of "Automatic Contrivance"

A)       To prevent over winding

B)       none of the above

C)       All of the above

D)       To prevent over speeding

E)       To prevent descending cage from being landed at speed exceeding 1.5 m/sec.

15)      Overspeeding of coal tubs can be restricted by   

A)       Friction wheel

B)       Jazz rail

C)       None of these

D)       Driving wheel

E)       Mono rail

16)      Among Wide & Stall, Knife Edge, Bhaska and Tipong_________are underground coal mining methods.

A)       All of the above

B)       only Wide & Stall, Bhaska & Tipong

C)       only Wide & Stall, Bhaska & Knife Edge

D)       only Wide & Stall, Knife Edge & Tipong

E)       only Wide & Stall, Knife Edge

17)      Fencing shall be erected and maintained around the excavation, if any mining operation, extends within a distance of______meters from a public road or any building .

A)       45

B)       60

C)       30

D)       15

E)       90

18)      Approximate explosive charge per hole for a 150 mm dia hole, 4m stemming height in a 12 m high overburden bench immediately above the coal seam with ANFO as column charge is     .

A)       310 kg

B)       110 kg

C)       160 kg

D)       210 kg

E)       175 kg

19)      Protodyakonov index of Indian coals varies from  to        

A)       4 ; 6

B)       1; 4

C)       10; 12

D)       6; 8

E)       8; 10

20)      The Factor of Safety selected while designing the size of pillar would be  .

A)       7.0 – 8.0

B)       2.2 – 2.4

C)       3.5 – 3.7

D)       5.0 – 5.2

E)       10

21)      Tell tale is           used in underground coal mine for         .

A)       an instrument; strata dilation

B)       an instrument; measure support efficieny

C)       an instrument; erecting hydraulic prop

D)       a method; erecting roof bolt

E)       a method; showing roof load

22)      In an opencast mine bench failure has occurred in which a triangular portion has come out. The type of failure is

A)       toppling up

B)       curved failure

C)       linear failure

D)       wedge failure

E)       None of these

23)      Adequacy of support in a longwall face can be assessed by comparing the         with rated support capacity.

A)       maximum load density

B)       marginal load density

C)       optimum load density

D)       mean load density

E)       minimum load density

24)      The peak abutment load found in a longwall panel working at 300m depth will be at   .

A)       50 ahead of the face

B)       1-5m ahead of the face

C)       450m ahead of the face

D)       300m ahead of the face

E)       150m ahead of the face

25)      Adjusted RMR is obtained for a depth of working ranging from 400-600m by reduction in %age in calculated RMR

A)       20

B)       None of these

C)       30

D)       15

E)       10

26)      The method suitable for working seam under workings of another seam which is water logged or in fire is

A)       none of them

B)       hydraulic maining

C)       long wall advancing

D)       long wall retreat

E)       bord and pillar

27)      Operational factors effecting the convergence at longwall face

A)       All of these

B)       Method of winning coal

C)       Cycle of work

D)       Rate of face advance and type of support

E)       Method of winning coal and Rate of face advance and type of support

28)      Slop failure of a waste rock dump does not depends on    of the rock.

A)       Compressive strength

B)       Shear Strength

C)       Bulk density

D)       Permeablity

E)       Porosity

29)      The design of the pit-top and pit bottom layout is done with the following objects in view -------

A)       Minimum decking time

B)       Use of the shaft to its full capacity

C)       Use of minimum number of tubs in the circuit

D)       Distance of dischrge of mineral

E)       All of these

30)      The bord and pillar method of mining is suited to work       coal seams of  m thick

A)       Flat, 2.8

B)       none of the above

C)       Incline, 4

D)       Incline, 1

E)       Incline, 2.5

31)      What will be the caving height if a 3 m thick flat coal seam depillared to full thickness and the caved roof in goaf has a bulking factor of 1.3   

A)       10 m

B)       8 m

C)       15 m

D)       13 m

E)       5 m

32)      A surface coal mine is worked by 12 m3 shovel – 100 tonne dumper combination. If the shovel bucket fill factor is 0.8, the material swell factor is 0.75 and the average in-situ sp.gr. of the material is 2.8 tonne/m3, the number of shovel bucket loads required to fill a dumper will be nearly     

A)       4

B)       7

C)       5

D)       6

E)       3

33)      In case of surface mine blast design

1.        The burden depends on depth and diameter of blasthole.

2.        The burden depends on rock type and charge length.

3.        Hole depth depends on bench height

A)       Only 3 is correct

B)       Only 1 and 3 are correct

C)       Only 1 and 2 are correct

D)       Only 2 and 3 are correct

E)       All the Options correct

34)      Risk of Air Blast increases in case of        .

A)       Coal seam is partially extracted with stowing

B)       coal mining with caving under massive roof

C)       Coal seam is depillared in conjunction with stowing.

D)       None of the above

E)       Coal seam is partially extracted.

35)      Which types of bench failure are hardly found ?

A)       Circular

B)       Plane

C)       Steps

D)       Toppling

E)       Wedge

36)      The maximum air velocity in a third degree gassy seam within 4.5m from any face shall not be less than

A)       15m/min

B)       30m/min

C)       45m/min

D)       60m/min

E)       90m/min

37)      In longwall mining advance supporting of gate roads upto 30 m from the face is required due to     .

A)       Yielding Pressure

B)       Advance Load

C)       Back Abutment pressure

D)       Side abutment pressure

E)       Front Abutment Pressure

38)      The percentage of extraction of coal from a pillar of 30m x 30m centre to centre with roadways 4m wide is

A)       28

B)       25

C)       30

D)       22

E)       35

39)      On every tub there shall be provided and maintained at each coupling end a strong buffer projecting beyond the end and so arranged that when two such tubs are in tandem, the gap between the innermost ends shall not be less than

A)       30 cm

B)       20 cm

C)       60 cm

D)       40 cm

E)       50 cm

40)      The co-efficient of friction winder should not less than      

A)       0.3

B)       0.25

C)       0.15

D)       0.2

E)       3.5

41)      The roof bolt density in a roof with a rock load L,factor of safety S and bolt capacity T is

A)       TXL/S

B)       LXT/S

C)       TXS/L

D)       LXS/T

E)       None

42)      Positive Set Valve is used to overcome the operator error in         

A)       Blast hole drilling machine

B)       Roof bolting machine

C)       Surface miner

D)       Powered roof support

E)       Shearer

43)      For Multi-section and contiguous working, the parting left between any two seams or sections shall not be less than …… meters in thickness at any place.

A)       4.5 m

B)       6 m

C)       2 m

D)       3 m

E)       9 m

44)      The magazine should be away from all bullidings by at least

A)       120m

B)       50m

C)       75m

D)       95m

E)       1 KILOMETER

45)      As per the DGMS(S&T)/(Tech.)Circular No.01/2017, in longwall mining method, if there is no automatic continous monitoring system of closure of Powered Roof Supports (PRS), measurmrnt of convergence (leg closure) of the PRS shall be carried out by tape measurment at least once in ….. during idle period and in other cases once in…..

 A)      Every shift, Every day

B)       Every day, Every month

C)       Every week, Every month

D)       Every day, Every week

E)       Installation of continuous monitoring system is mandatory .

46)      Temperature increases with respect to increase in depth due to   

A)       Geochemical Gradient

B)       Geomechanical gradient

C)       Increase in rock density

D)       Geostatic gradient

E)       Geothermal gradient

47)      What should be the minimum quantity of horizontal illumination in general working areas and rest shelter in opencast mines ,respectively.

A)       15 lux and 25 lux

B)       2 lux and 5 lux

C)       10 lux and 30 lux

D)       20 lux and 30 lux

E)       5 lux and 10 lux

48)      Where sand stowing is done a statement showing the quantity of coal produced and quantity of sand stowed shall be submitted to DGMS

A)       Once in 12 months

B)       None of these

C)       Once in 3 months

D)       Once in a month

E)       Once in 6 months

49)      No. of boreholes per sq. km. required for undeground and surface coal mining respectively are    and       .

A)       6-8, 10-12

B)       6-8, 12-14

C)       1-2, 4-6

D)       2-4, 4-6

E)       4-6, 10-12

50)      Diesel locomotives are not allowed where CH4 percentage exceeds  in general body of air

A)       0.5 %,

B)       0.50%

C)       1.25%

D)       1%

E)       0.75%

51)      Which one of the following is most common type of slope failure for waste dump?

A)       Steps

B)       Plane

C)       Wedge

D)       Circular

E)       Toppling

52)      Mining of coal seam lying at 120 m depth by bord and pillar method permits formation of pillars as small as     .

A)       25.5m x 25.5m (centre to centre) surrounded by galleries of 4.8m wide

B)       12.5m x 12.5m (centre to centre) surrounded by galleries of 3 m wide

C)       30.5m x 30.5m (centre to centre) surrounded by galleries of 4.2m wide

D)       34.5m x 34.5m (centre to centre) surrounded by galleries of 4.8m wide

E)       15.5m x 15.5m (centre to centre) surrounded by galleries of 4.2m wide

53)      What wll be the approximate carrying capacity of belt conveyorof 1200 mm width if load cross section area of the belt conveyor is 0.15 sq. m, belt speed is 2.5m/s and the bulk density of coal is 1.5 t/cum ? Consider a reducing factor due to 10 degree inclination of belt is 0.95.

A)       1900

B)       1500

C)       1700

D)       2100

E)       2500

54)      In the Moh's scale of hardness, the minerals in increasing sequence of hardness are

A)       topaz, gypsum, calcite, diamond

B)       None of the above

C)       gypsum, calcite, topaz, diamond

D)       calcite, gypsum, diamond, topaz

E)       calcite, gypsum, topaz, diamond

55)      In favorable geomining condition, for high production and high productivity mechanised mining of flat to gently dipping, 1.5 to 4.5 m thick coal seams, the most suitable method is      

A)       Longwall Mining

B)       Bord & Pillar Mining

C)       Room & Pillar Mining

D)       Knife Edge Method

E)       Blasting Gallery Method

56)      The type core-barrel normally used in diamond drilling for obtaining RQD is           .

A)       Options B and C

B)       Options A and C

C)       Double tube

D)       Triple tube

E)       Single tube

57)      The weight of the rocks in coal mining areas exerts a pressure nearly per metre depth from surface is per

A)       1kg per sqcm

B)       0.2kg/sqmm

C)       0.2kg per sqcm

D)       0.5kg per sqcm

E)         0.2 kg per sqmm

59)      Match the following

            Title                                                      Regulation No.

           1.Notice of opening                                             a.3

           2.Notice of reopening                                          b.6

           3.Notice of disease                                             c.5

           4.Notice of closure                                              d.9

A)       1-c, 2-b, 3-d, 4-a

B)       1-a, 2-b, 3-c, 4-d

C)       None of the above

D)       1-b, 2-1, 3-d, 4-c

E)       1-a, 2-b, 3-d, 4c

60)      In a fully mechanized bord and pillar mining system, winning of coal and its transportation from the face is commonly carried out with the combination of

A)       continuous miner, SDL, feeder breaker and belt conveyor

B)       continuous miner, LHD, feeder breaker and chain conveyor

C)       continuous miner, shuttle car, feeder breaker and chain conveyor

D)       None of the above

E)       continuous miner, shuttle car, feeder breaker and belt conveyor

61)      A double ended ranging drum shearer operates in a longwall retreating panel. The following data re provided:Face length : 200 m, Average cutting speed : 1.5m/min, Web depth : 0.6 m, Average flitting speed : 4.0 m/min, Cutting height: 2.5 m, Number of shifts/day : 3, Density of coal : 1.4 tonne/cu.m.Method of cutting is unidirectional and each shift requires a non-operational time of 2.0 hours. The production per day in tonne (rounded off to one decimal place) is ------

A)       2000.5 to 2001.2

B)       2200.5 to 2250.2

C)       None of the above

D)       2450. to 2550.5

E)       3000.1 to 3250.5

62)      Following information about a longwall retreating panel is given. Panel length = 1800 m, Face length = 150 m, Depth of web = 0.6 m, Shearer travels at a speed of 1.5 m/min along the face. Each cutting cycle requires a non- operational time of 2 h. 20 min. The panel is fuly extractable. The number of working days required to extract the panel is   

A)       700

B)       500

C)       750

D)       600

E)       450

63)      In an undergrond working area, H2 and CO2 found near to the

A)       Floor & roof

B)       Floor & floor

C)       Roof & roof

D)       Roof & floor

E)       none of the above

64)      Typical diameter range of sylindrical rock sample used for strength test is          

A)       10-25 mm

B)       25-50 mm

C)       50-75 mm

D)       100-125 mm

E)       75-100 mm

65)      The property that cannot be determined from uniaxial compressive strength test of a rock sample fitted with strain gauge is

A)       Cohesion

B)       Dilation

C)       none of the above

D)       Modulus of elasticity

E)       Poisson ratio

66)      Which of the following parameter is not used to classify a rock mass using the RMR ?

A)       Condition of discontinuities

B)       Ground water condition

C)       Uniaxial compressive strength of rock

D)       Spacing of discontinuities

E)       Tensil strength of rock

67)      Which of the fillowing is not a field equipment where Operator Independent Truck Dispatch System adopted ?

A)       Data radio unit

B)       LCD display pannel

C)       GPS

D)       Communication server

E)       VSMS unit

68)      Exposure of weak roof in junctions of a development district in a coal mine can be decreased by

A)       staggering the junctions

B)       increasing dimension of panel barrier

C)       increasing support density at junctions

D)       stitching side walls

E)       None of the above

69)      If the thickness of immediate roof is more than     mtr., the roof of underground coal mine become stronger and behave like a main roof ,

A)       5

B)       4

C)       3

D)       6

E)       2

70)      Parting between contiguous seams shall be

A)       Not less than 2.5m and not more than 7.5m

B)       Not less than 3m and not more than 9m

C)       Not less than 2.0m and not more than 9.5m

D)       Not less than 2.2m and not more than 7.5m

E)       None of these

71)      The size of the gallery & pillar varies with the depth of the mine. Which of the statements are true

A)       At same depth the wider the gallery, the larger should be the pilar size.

B)       none of them are true

C)       the gallery width increases with decrease in pillar size

D)       For the same gallery width, the size of the pillar increases with depth.

E)       A & B both are true

72)      Which of the following is the most advanced system for monitoring of pit and dump slope in opencast mines ?

A)       Radar monitoring system

B)       Satelight monitoring system

C)       DGPS monitoring system

D)       GPS monitoring system

E)       Leaser scanner monitoring system

73)      No working shall be made in any mine any spot lying within a horizontal distance of         meters from either bank of a river or canal or from the boundary of a lake, tank or other surface reservoir except with the previous permission in writing of the Chief Inspector.

A)       60 m

B)       45 m

C)       15 m

D)       10 m

E)       30 m

74)      The borehole extensometer is used for    

A)       Measure the deformation in roof rock

B)       Used in core sample preparation machine to measure the compressive strength of rock

C)       Measure the length of core during core drilling

D)       Core recovery in diamond core drilling

E)       Measure the temperature of drill hole to be used for blasting

75)      A 10 m thick coal block is excavated by a contractor at a cost of Rs.40 per cu.m. The excavated area, measured in the mine plan, is found to be 50 sq.cm. If the mine plan has been drawn to a scale of 1:1000, the payment to be made to the contractor, in lakhs of Rs., is ------

A)       23

B)       25

C)       26

D)       20

E)       18

76)      A flat longwall panel is mined out at an area having subsidence factor a. The measured maximum subsidence on the surface is S for a mining height of m. The subsidence is subcritical if

A)       S = am

B)       None of the above

C)       S < am

D)       S > am

E)       S = m/a

77)      Horzontal slicing method is applied if the seam thickness is

A)       less than 5m

B)       more than 15m

C)       more than 10m

D)       less than 15 m

E)       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 method

A)       P-3, Q-4, R-1, S-2

B)       P-3, Q-4, R-2, S-1

C)       P-1, Q-4, R-2, S-3

D)       P-3, Q-2, R-1, S-4

E)       None of the above

79)      Ward - Leonard system is provided in the winding system in order to restrict

A)       Over speeding of cage

B)       Acceleration of the cage

C)       Over winding of the cage

D)       Deceleration of the cage

E)       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 these

C)       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 rocks

B)       Highly abrasive and low strength rocks

C)       Medium strength and non-abrasive rocks

D)       Very Strong and abrasive rocks

E)       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, 30m

B)       60m, 30m

C)       30m, 15 m

D)       45 m, 15m

E)       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 explosive

B)       3 tonne /kg of explosive

C)       4 tonne /kg of explosive

D)       2 tonne /kg of explosive

E)       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 treatment

A)       P-3, Q-1, R-4, S-2

B)       P-4, Q-3, R-1, S-2

C)       P-3, Q-4, R-1, S-2

D)       None of the above

E)       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; conservation

B)       safety; production; productivity

C)       conservation; safety; environment

D)       safety; conservation; productivity

E)       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 tonne

B)       2.2 tonne

C)       1.6 tonne

D)       2.0 tonne

E)       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 above

D)       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 3.1

B)       2.0 to 2.1

C)       None of the above

D)       1.4 to 1.6

E)       3.8 to 4.0

89)      Bench failure is caused by

A)       linear tension

B)       all of these

C)       two tensions in inclined directions

D)       multi-directional tensions

E)       over-loading

90)      Which of the following is not a general mode of slope failure?

A)       Shear failure

B)       Rotational failure

C)       Planar failure

D)       Toppling failure

E)       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/m2

B)       2.0 t/m2

C)       3.0 t/m2

D)       1.5 t/m2

E)       2.5 t/m2

92)      Support system design based on RMR depends on the following   .

A)       width of gallery

B)       method of excavation

C)       Depth of seam

D)       Roof rock load density

E)       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 be

A)       6.5

B)       5.5

C)       5

D)       6

E)       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 be

A)       600

B)       500

C)       450

D)       400

E)       550

95)      At the nozzle in hydraulic mining operation, what should be the minimum pressure to be maintained

A)       5-10 kgf/sq.cm.

B)       15-20 kgf/sq.cm.

C)       40-100 kgf/sq.cm.

D)       21-35 kgf/sq.cm.

E)       10-20 kgf/sq.cm.

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)       15

B)       30

C)       45

D)       25

E)       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 pillar

A)       P-4, Q-3, R-1, S-2

B)       P-2, Q-3, R-4, S-1

C)       None of the above

D)       P-2, Q-3, R-1, S-4

E)       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 cum

B)       45750 cum

C)       371790 cum

D)       427860 cum

E)       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 bits

A)       P-3, Q-4, R-2, S-1

B)       P-2, Q-4, R-3, S-1

C)       None of the above

D)       P-2, Q-3, R-4, S-1

E)       P-4, Q-2, R-3, S-1

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