21. The stowing efficiency in penumatic stowing is
22. Broken working referred as
23. The hydraulic prop built up its full bearing load with an yield less than . . . . . . . . cm.
24. The roof fall which is not extended to surface
25. The parting between two horizons must not be less than . . . . . . . .
26. The limit of depth use of screw feed mechanism
27. The section of the curbing segments are
28. Jack hammer operates at an air pressure of nearly
29. In a gallery of 4.2 m width and 2.1 m height and 1 m depth, sp.gr. of coal is 11; the coal available for blast is for four rounds of solid blasting.
30. Reduce the friction of the rock to the passage of cement certain types of rocks
Read More Section(Coal Mining)
Each Section contains maximum 100 MCQs question on Coal Mining. To get more questions visit other sections.