31.
Match the following, for standard diamond rods
Specification Outer diameter in mm
P. AW p. 34.9
Q. BW q. 44.4
R. EW r. 54.0
S. NW s. 66.7

33.
A vertical ore body having a consistent width of 100 m has been excavated by the open pit method up to a depth of 100 m at a pit slope angle of 45°. The figure shows the cross section of the open pit. If the ore body is further excavated by a depth of 10 m, maintaining the same pit slope angle, the ratio of waste rock to ore is
Introduction to Mining Engineering mcq question image

36.
Shale as immediate roof in underground, coal mine is not suitable because

39.
In an opencast mine shown in the figure below, the coal has a density of 1.4 t/m3. Assuming mining operation started from plane XY, the operating stripping ratio under the given conditions in m3/t is
Introduction to Mining Engineering mcq question image