71. Splitting may start from . . . . . . . . middle points of pillar simultaneously.
72. Strata through which shaft has to be sunk may be divided into
73. Diamond drill bit is rotated at a speed of nearly
74. The pressure falling on drill bit can be controlled during drilling by
75. The methods used deflection of bore holes are
76. The discharge velocity of sand in pneumatic stowing in m/s . . . . . . . .
77. Manual drilling is possible upto maximum
78. For deep hole, downward holes, for blasting in quaries, the type of drilling preferred are
79. Pocket wheel stowing machines also called
80. Lump breaker installed near belt conveyor to reduced the coal to . . . . . . . . size.
Read More Section(Coal Mining)
Each Section contains maximum 100 MCQs question on Coal Mining. To get more questions visit other sections.