Mining Engineering Gate 2020 Questions with Answer

Ques 40 GATE 2020

A cylindrical sample of cross-sectional area A, length L, and Young's Modulus E, is subjected to a constant uniaxial load P. Within the elastic limit of loading, the total strain energy stored is

Ques 41 GATE 2020

A surface mine production system along with the reliability of the individual components is shown below. The system reliability is ________. (round off to 3 decimal places).

Ques 42 GATE 2020

Two underground mines are separated by a horizontal coal barrier of 60 m thickness. One mine is inundated, whereas the other mine has a blind heading of dimensions 4.0 m wide and 2.5 m height terminating at the barrier. The overall in-situ shear strength of the coal mass is 500 kPa. Assume that the failure mode is in shear. At a factor of safety of 10, the maximum water head that can be withstood by the coal barrier, in m, is ___________. (round off to 1 decimal place).

Ques 43 GATE 2020

Air enters from ambient atmosphere into a level duct of uniform cross-section area 0.2 m² at a flow rate of 2.0 m³/s and density of 1.2 kg/m³. The entry shock loss factor is 1.0 and the resistance of the duct per meter length is 1.0 Ns²/m⁸. The static pressure measured at a distance of 20 m from the duct entrance in Pa, is __________. (round off to 1 decimal place).

Ques 44 GATE 2020

A sealed-off area air sample consists of 16.0% O₂ 3.0% CO₂ and the rest is N₂. Assume that the standard composition of atmospheric air is 21.0% O₂ and 79.0% N₂ The percentage of blackdamp in the air sample is ___________. (round off to 2 decimal places).

Ques 45 GATE 2020

A diesel loader produces 60 l/s of exhaust fumes containing 5000 ppm of CO. The incoming air has 10 ppm of CO. The minimum amount of air flow in m³/s that is needed at the loader to dilute CO to a permissible level of 50 ppm is _________. (round off to 1 decimal place).

Ques 46 GATE 2020

The equation for peak particle velocity (PPV) from blast induced ground vibration is given by
PPV=k(D/√Q)^B. where k and B are site constants.
In a field study, the following readings are recorded.

Ques 47 GATE 2020

An underground copper mine sends 2500 tonnes of ore per day to the concentrator plant having an average grade of 1.2% Cu. The plant produces concentrate of 25.0% Cu with a recovery of 93.0%. The solids portion of tailings generated from the plant per day in tonnes is __________. (round off to 1 decimal place).

Ques 48 GATE 2020

A mine gallery is supported by regularly placed roof bolts of 100 kN allowable pull force per bolt, as shown below. Assuming unit weight of the immediate roof is 25 kN/m³, the factor of safety of the support system is _________. (round off to 2 decimal places).

Ques 49 GATE 2020

The slip circle of radius 30.0 m in an overburden slope is shown with the centre of slip circle at point O. The tension crack is completely filled with water. For one meter width of the slope, the moment exerted by the force of water about O in kN-m is _______.(round off to 1 decimal place).

Ques 50 GATE 2020

For a development heading, the blasting parameters are
Cross-section: 6.0 m×5.0 m
Total number of holes: 72
Number of trimmer holes: 30
Depth of each hole: 3.5 m
Charge per hole (except trimmers): 3.5 kg
Charge per trimmer hole: 1.8 kg
Pull per round: 90% of hole depth
The powder factor for the development round in m³/kg is ___________. (round off to 2 decimal places).

Ques 51 GATE 2020

The following figure represents the observations from the level survey of an underground gallery.

Ques 52 GATE 2020

A tacheometer was setup at station P and the following readings were taken at two stations A and B with the staff held vertical and the line of sight horizontal.