Mining Engineering Gate 2022 Questions with Answer

Ques 53 GATE 2022

The extraction ratio during development of a bord and pillar panel is 0.15 in a flat coal seam. The panel is further extracted by widening the galleries, and the extraction ratio changes to 0.25. The percentage change in pillar stress, considering tributary area method, is ____________. (round off to two decimal places)

Ques 54 GATE 2022

In a small metal mine a battery powered locomotive hauls a train of mine tubs such that:
The weight of the train of mine tubs, tonne: 3.0
The coefficient of friction between the wheels and the rails: 0.06
The coefficient of adhesion between the loco wheels and the rails: 0.2
Time required from the start to reach speed of 1.8 m/s through constant acceleration, min: 3.0
Upward gradient to be negotiated: 1 in 20
The minimum weight of the locomotive in tonnes to meet these design requirements, is _________. (round off to one decimal place)

Ques 55 GATE 2022

A pump lifts mine water of density 1020 kg/m³, at 250 m³/hr from a depth of 150 m. The overall pumping efficiency is 68%. Considering a head loss of 15 m due to pipe friction and shock, the motor input power, in kW is _________. (round off to two decimal places)

Ques 56 GATE 2022

In a surface mine bench, overburden is removed by the shovel-dumper combination. For the dumper:

Ques 57 GATE 2022

In a bord and pillar development panel, headings of 4.4 m×2.5 m are advanced using solid blasting. The average pull per round of blast is 1.2 m. On an average 12 faces are blasted per day. Density of coal is 1500 kg/m³. The mine operates in three shifts. If the average daily employment is 330 persons, labour productivity (OMS) of the panel in tonne, is ________. (round off to two decimal places)

Ques 58 GATE 2022

In a longwall face, the full seam thickness of 3 m is cut by a shearer with a web of depth 0.7 m. The hauling speed of shearer during cutting is 12 m/min. The trough cross-section of AFC is 0.4 m² and the average loading coefficient is 0.7. In order to evacuate coal from the face without spillage, the speed of AFC, in m/s is ________. (round off to one decimal place)

Ques 59 GATE 2022

A city is spread over an area of 20 km×40 km. Wind, at an average speed of 4 m/s, enters perpendicular to the 20 km long side. On a winter day the inversion layer exists over the city at a height of 100 m. PM1 is emitted from the city at a rate of 1 kg/s. The steady state PM₁ concentration in the city air, in μ g/m³, assuming Box model, is _________. (round off to one decimal place)

Ques 60 GATE 2022

The point 'A' as shown in the Coward flammability diagram represents the gas composition of a sealed-off area of a coal mine. The volume of the sealed-off area is 10000 m³. Inert gas is proposed to be injected into the sealed-off area so that the gas composition comes below the LEL (lower explosibility limit). The minimum volume of the inert gas required (at the same pressure as that of the sealed-off area), in m³ is __________. (round off to one decimal place)

Ques 61 GATE 2022

An underground workshop has dimensions of 8 m length, 6 m width and 4 m height. Four identical luminaires are placed at the four corners of the roof. Each luminaire is of 100 W capacity with luminous efficacy of 100 lumen/W Light is transmitted spherically from luminaires and there are no reflections. The illumination on the horizontal plane at the centre of the floor, in lux is _________. (round off to two decimal places)

Ques 62 GATE 2022

An intake shaft has resistance of 0.05 Ns²/m⁸ up to a depth of 400 m. The airflow rate is 100 m³/s and the average density is 1.2 kg/m³ A barometer reads 99.375 kPa when placed on surface. Considering acceleration due to gravity is 9.81 m/s², the reading of the barometer at the depth of 400 m, in kPa is _____________.(round off to two decimal places)

Ques 63 GATE 2022

The net present values (NPV) of two mining project proposals A and B are as given.
NPV_A=-0.01i²-0.02i+4.44
NPV_B=-0.03i²-0.01i+6.55
where, i is discount rate.
The required rate of return for which both the proposals have equal possibility of acceptance and rejection, is _________. (round off to two decimal places)

Ques 64 GATE 2022

A coal seam of uniform thickness 12 m is dipping at an angle 30° as shown in the figure. The ultimate pit is demarcated based on allowable instantaneous stripping ratio of 10 m³/tonne and safe slope angle of 45°. The density of coal is 1.41 tonne/m³. The length, L in m is _________. (round off to two decimal places)

Ques 65 GATE 2022

A mine has a reserve of 150 million tonne (Mt) and is designed for a maximum production capacity of 5 Mt per year. In the first year the production is 2 Mt and it increases by 20% each year. The reserve in Mt that remains at the end of 15 years, is _________. (round off to two decimal places)