Underground Coal Mining Technology Mid - II, November - 2014

1.The average number of face in a district with no of headings is
  • (n-1)
  • (2n-1)
  • (n-2)
  • (3n-2)
Answer: B
2.A gallery driven in the pillar for the purpose of extraction is called
  • Stools
  • Slice
  • Split
  • Barrier
Answer: C
3.The roof fall which affects the surface is known as
  • Local fall
  • Mainfall
  • Normal fall
  • Premature collapse
Answer: B
4.Generally longwall method of working is adopted for
  • Thin seams
  • moderate seams
  • thick seams
  • very thick seams
Answer: A
5.As per reg the minimum size of pilar required for the seam whose depth is 360mtrs and above
  • 34.5mts
  • 45.0mts
  • 48.0mts
  • 54.0mts
Answer: C
6.The roads at either end of the longwall face are known as
  • Supply gate
  • Tail gate
  • Haulage gate
  • Gate roads
Answer: D
7.Headings advancing in a direction of right angles to the main cleat are called
  • Walls
  • Bords
  • End places
  • Levels
Answer: B
8.For easy turn round of locomotives at corners the pillars are
  • Square
  • Rectangular
  • Triangular
  • Rhombus
Answer: D
9.Bord and pillar method of working is adopted for the seams whose depth is
  • Shallow
  • Moderate
  • Deep
  • Very deep
Answer: B
10.If seams are separated by a partition of 9m, they are known as
  • Contiguous seams
  • Split seams
  • Splinter seams
  • Multi seams
Answer: A
11.The maximum height of gallery permitted is ......................
Answer: 3m
12.The displacement of air, in the goaf when the roof fall takes place is called ...........................
Answer: Main fall
13.Filling the void formed by extraction of coal, with combustible material is called .........................
Answer: Stowing
14.A line passing through all the corners of stook under extraction is called ........................
Answer: Line extraction
15.With the pneumatic stowing, the economic limit of pipeline is in the region of .................................
Answer: 200mm
16.In the layout of locomotives and mine cars, the operating distance of shuttle cars is limited to .....................
Answer: 180m
17.Bord and pillar method of working is applicable for seams ...................
Answer: 1:6m
18.In longwall advancing stables are usually ...................... a head the face.
Answer: 8 to 10
19.The pillars formed during development are split into small pillars are called .................
Answer: Stook
20.Generally the ratio H:L for reasonably good stowing ratio is .............
Answer: 1/7