71. Any clay or shale which does not fuse, below 158°C called
72. Number of holes required to errect a timber bar
73. Chock shields can work in steeply inclined seams upto maximum . . . . . . . . deg.
74. Bulk strength of the timber prop is . . . . . . . . kg/cm2.
75. If the prop has to be set on loose rock, it should be placed on . . . . . . . .
76. The pressure arch in longwall workings have its apex or crest at a mm height above the seam at nearly . . . . . . . . times the length of face.
77. First aid certificate is not required for
78. The load does not effect the load yeild characteristic of the prop.
79. In which contains separated pre-measured quantity of filled polyestered and resin catalyst called
80. Timber bar placed in the holes of minimum depth of . . . . . . . .
Read More Section(Mine Supports and Strata Control)
Each Section contains maximum 100 MCQs question on Mine Supports and Strata Control. To get more questions visit other sections.