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General Aptitude

10 Questions
GATE→2023→General Aptitude→Verbal Ability
Q1
MCQ[1 Mark]
The line ran ________ the page, right through the centre, and divided the page into two.
GATE→2023→General Aptitude→Verbal Ability
Q2
MCQ[1 Mark]
Kind : ________ :: Often : Seldom (By word meaning)
GATE→2023→General Aptitude→Quantitative Aptitude
Q3
MCQ[1 Mark]
In how many ways can cells in a 3×33\times3 grid be shaded, such that each row and each column have exactly one shaded cell? An example of one valid shading is shown.
Figure for Question 3
GATE→2023→General Aptitude→Quantitative Aptitude
Q4
MCQ[1 Mark]
There are 4 red, 5 green, and 6 blue balls inside a box. If N number of balls are picked simultaneously, what is the smallest value of N that guarantees there will be at least two balls of the same colour?
GATE→2023→General Aptitude→Quantitative Aptitude
Q5
MCQ[1 Mark]
Consider a circle with its centre at the origin (O), as shown. Two operations are allowed on the circle. Operation 1: Scale independently along the x and y axes. Operation 2: Rotation in any direction about the origin. Which figure among the options can be achieved through a combination of these two operations on the given circle?
Figure for Question 5
GATE→2023→General Aptitude→Verbal Ability
Q6
MCQ[2 Marks]
Elvesland is a country that has peculiar beliefs and practices... Based only on the information provided above, which one of the following sets of statement(s) can be logically inferred with certainty? (i) In Elvesland, one always declares one's love by gifting a white flower. (ii) In Elvesland, all emotions are declared by gifting flowers. (iii) In Elvesland, sometimes one expresses one's anger by gifting a flower that is not yellow. (iv) In Elvesland, sometimes one expresses one's love by gifting a white flower.
GATE→2023→General Aptitude→Quantitative Aptitude
Q7
MCQ[2 Marks]
Three husband-wife pairs are to be seated at a circular table that has six identical chairs. Seating arrangements are defined only by the relative position of the people. How many seating arrangements are possible such that every husband sits next to his wife?
GATE→2023→General Aptitude→Verbal Ability
Q8
MCQ[2 Marks]
Based only on the following passage, which one of the options can be inferred with certainty? [Excerpt from These Hills Called Home by Temsula Ao]
GATE→2023→General Aptitude→Quantitative Aptitude
Q9
MCQ[2 Marks]
If x satisfies the equation 48x=2564^{8^{x}}=256, then x is equal to
GATE→2023→General Aptitude→Quantitative Aptitude
Q10
MCQ[2 Marks]
Consider a spherical globe rotating about an axis passing through its poles. There are three points P, Q, and R situated respectively on the equator, the north pole, and midway between the equator and the north pole in the northern hemisphere. Let P, Q, and R move with speeds vPv_{P}, vQv_{Q}, and vRv_{R}, respectively. Which one of the following options is CORRECT?

Engineering Mathematics

10 Questions
GATE→2023→Engineering Mathematics→Vector Calculus
Q11
MCQ[1 Mark]
Given two vectors A⃗=3i^+2j^\vec{A}=3\hat{i}+2\hat{j} and B⃗=i^+j^\vec{B}=\hat{i}+\hat{j}, the magnitude of projection of A⃗\vec{A} along B⃗\vec{B} is
GATE→2023→Engineering Mathematics→Probability and Statistics
Q12
MCQ[1 Mark]
Given two random variables X and Y, the expected value E(3X−5Y)E(3X-5Y) is
GATE→2023→Engineering Mathematics→Calculus
Q13
MCQ[1 Mark]
xx and yy are functions of independent variables rr and θ\theta as given below: x=r cos θx=r~cos~\theta, y=r sin θy=r~sin~\theta. The Jacobian of x,yx, y is
GATE→2023→Engineering Mathematics→Linear Algebra
Q14
MCQ[1 Mark]
Matrix A is negative definite. Which one of the following is NOT the correct statement about the matrix?
GATE→2023→Engineering Mathematics→Probability and Statistics
Q15
MCQ[2 Marks]
In a quality control process of coal supplied to a thermal plant, the 3-sigma control limits for fixed carbon (FC) are defined by 40%±15%40\%\pm15\%. The process is termed "out of control" if: Rule 1: 4 out of 5 successive values... Rule 2: Any one value crosses any of the 3-sigma control limits. For the continuous data: 49, 51, 56, 20, 46, 48, 47, 49, 45, 41, 42, 40, the process is
GATE→2023→Engineering Mathematics→Calculus
Q16
MCQ[2 Marks]
The evaluation of the integral I=∫ex−1+xe−1ex+xedxI=\int\frac{e^{x-1}+x^{e-1}}{e^{x}+x^{e}}dx yields
GATE→2023→Engineering Mathematics→Calculus
Q17
MCQ[2 Marks]
Given the function f(x)=∣x∣+∣x−1∣f(x)=|x|+|x-1|. For all the real values of x, which one of the following statements is CORRECT?
GATE→2023→Engineering Mathematics→Linear Algebra
Q18
MCQ[2 Marks]
The slope and intercept values of three linear equations are given... The above system of equations has
GATE→2023→Engineering Mathematics→Probability and Statistics
Q19
MCQ[2 Marks]
A regression line is constructed between shovel production rate and shovel swing angle for 50 observations as shown below... If residuals are normally distributed and significance tests of the parameters are conducted at 0.05 significance level, the true statement is
Figure for Question 19
GATE→2023→Engineering Mathematics→Probability and Statistics
Q20
NAT[2 Marks]
The time between consecutive accidents in days in an underground coal mine in a year are as follows: 10, 15, 6, 18, 12, 14, 16, 9, 21, 15, 26, 18, 22, 25, 13. Assuming exponential distribution, the probability that there will be no accident over a 10-day period is [rounded off to 2 decimal places]

Mining Geology, Mine Development and Surveying

8 Questions
GATE→2023→Mining Geology, Mine Development and Surveying→Mining Geology
Q21
MCQ[1 Mark]
The fault pattern shown in the figure is a case of
Figure for Question 21
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Development
Q22
MCQ[1 Mark]
The blast pattern of a coal face shown in the figure represents
Figure for Question 22
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Surveying
Q23
MCQ[1 Mark]
Match the following items with their respective contours
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Surveying
Q24
MCQ[1 Mark]
In an astronomical survey at a given station, the pole star is located at an angle of 27∘27^{\circ} from the horizon. The latitude of the survey station in degrees is
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Surveying
Q25
MCQ[1 Mark]
The position tracking of a point by GPS is based on the technique of
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Surveying
Q26
MCQ[2 Marks]
Match the following devices with their intended applications.
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Surveying
Q27
NAT[2 Marks]
Coordinate of two points A and B are (E 0 m, N 200 m) and (E 300 m, N 200 m), respectively. The bearing of two lines AO and BO are 67∘67^{\circ} and 35∘35^{\circ}, respectively. The easting of point O, in m, is [rounded off to 2 decimal places]
GATE→2023→Mining Geology, Mine Development and Surveying→Mine Development
Q28
NAT[2 Marks]
A surface mine blast pattern has spacing 4 m and burden 3 m. The diameter of the drill hole is 110 mm. The drilling length is 8.8 m including subgrade of 10%. The bulk explosive density is 900 kg/m3900\text{ kg}/\text{m}^{3}. If the powder factor is 2.5 m3/kg2.5\text{ m}^{3}/\text{kg}, the charge length in m is [rounded off to 2 decimal places]

Geomechanics and Ground Control

14 Questions
GATE→2023→Geomechanics and Ground Control→Engineering Mechanics
Q29
MCQ[1 Mark]
A shear stress τ\tau acts tangentially to the upper surface of a block and causes a small deformation Δw\Delta w as shown. The shear strain is calculated by
Figure for Question 29
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q30
MCQ[1 Mark]
Axial stress versus axial strain curves for two test results of a porous rock from triaxial undrained compression tests are shown in the figure. The pore pressure for the curve B can be the best explained by
Figure for Question 30
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q31
NAT[1 Mark]
A slope stability radar shows that the position of a point P in a mine dump shifts from (200, 700, -60) m to (200.05, 700.1, -60.75) m over a time Δt\Delta t. The net displacement in cm of the point P is [rounded off to 2 decimal places]
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q32
NAT[1 Mark]
A Mohr-Coulomb failure envelop of a sandstone rock is given as σ1=30+3.5σ3\sigma_{1}=30+3.5\sigma_{3} where σ1\sigma_{1} and σ3\sigma_{3}, measured in MPa, are the major and minor principal stresses respectively. The angle ofキュリティ the failure plane with the σ3\sigma_{3} axis in degree is [rounded off to 1 decimal place]
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q33
NAT[1 Mark]
A punch hole of diameter 10 mm is to be made in a 5 mm thick rock plate as shown. If the yield strength of rock plate is 25 MPa, the punch force P required in kN is [rounded off to 1 decimal place]
GATE→2023→Geomechanics and Ground Control→Subsidence
Q34
NAT[1 Mark]
Critical subsidence has occurred on the surface due to mining of a flat longwall panel at a depth of 200 m. The width of the panel is 150 m. The maximum width of the panel in m that can be mined at a depth of 300 m, to reach critical subsidence is [rounded off to 1 decimal place]
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q35
MCQ[2 Marks]
A tunnel of diameter 8 m is to be driven in a rock mass having quality index, Q of 1.0. Assume the excavation support ratio (ESR) of the tunnel is 1.0. The support requirement of the tunnel wall using fibre reinforced shotcrete (based on the chart prepared by Grimstad and Barton, 1993) is
Figure for Question 35
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q36
NAT[2 Marks]
A circular tunnel is developed in a biaxial in situ stress field as shown in the figure. If the ratio between tangential stress at the boundary point A and that at the boundary point B is 2.0, the value of k is [rounded off to 2 decimal places]
Figure for Question 36
GATE→2023→Geomechanics and Ground Control→Ground Control
Q37
NAT[2 Marks]
Strength of a rectangular coal pillar in MPa is given by Sp=S1(0.64+0.54wh−0.18w2lh)S_{p}=S_{1}(0.64+0.54\frac{w}{h}-0.18\frac{w^{2}}{lh}) where w, l(≥w)l(\ge w) and h are width, length and height of the pillar, respectively. A 30 m square pillar is split into two halves as shown. The height of the pillar is 3 m. The ratio of safety factors between one half-pillar and the original square pillar is [rounded off to 2 decimal places]
Figure for Question 37
GATE→2023→Geomechanics and Ground Control→Engineering Mechanics
Q38
NAT[2 Marks]
A dozer pushes up a 100 kg spool of cable along a 20∘20^{\circ} incline road at a constant velocity as shown in the figure. The coefficient of static friction between the dozer bucket and the spool (Point B) is 0.45, and coefficient of kinetic friction between road and the spool (Point A) is 0.15. Consider the spool only slides up the incline. The maximum normal force in N acting at Point B, is [rounded off to 1 decimal place]
Figure for Question 38
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q39
NAT[2 Marks]
Stress waves are sent from the transmitter A to the receiver B through an isotropic and elastic cylindrical rock specimen as shown in the figure. The length of the specimen is 100 mm. The travel time of longitudinal and shear waves are 0.025 ms and 0.04 ms, respectively. The Poisson's ratio of the rock specimen is [rounded off to 2 decimal places]
Figure for Question 39
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q40
NAT[2 Marks]
A jointed rock sample is subjected to 20 MPa vertical stress as shown in the figure. The modulus of elasticity of the rock is 10 GPa and the normal stiffness of the joint surface is 5 GPa/m5\text{ GPa/m}. Assuming one-dimensional elastic behaviour of rock and joint, the displacement in mm of the loading surface AB is [rounded off to 1 decimal place]
Figure for Question 40
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q41
NAT[2 Marks]
An irregular shaped rock sample of mass 60 g displaces 27 g of brine when submerged in a filled jar. The specific gravity of brine is 1.05. The unit weight of the rock sample in kN/m3\text{kN/m}^{3} is [rounded off to 2 decimal places]
GATE→2023→Geomechanics and Ground Control→Geomechanics
Q42
NAT[2 Marks]
A rock slope is intercepted by a joint plane at an angle 30∘30^{\circ} as shown in figure... Unit weight of rock = 20 kN/m320\text{ kN/m}^{3}, Cohesion of joint = 30 kPa, Friction angle of joint = 22∘22^{\circ}. The factor of safety of the rock slope to slide along the joint plane is [rounded off to 2 decimal places]
Figure for Question 42

Mining Methods and Machinery

7 Questions
GATE→2023→Mining Methods and Machinery→Mining Methods
Q43
MCQ[1 Mark]
A tabular, near-flat (dip<30∘dip<30^{\circ}), and less than 2 m thick copper orebody having erratically located grade is to be mined underground. Wall rock and orebody are competent. The most suitable mining method is
GATE→2023→Mining Methods and Machinery→Mining Machinery
Q44
NAT[1 Mark]
A coal seam of 3.0 m height is mined with a double-ended ranging drum shearer (DERDS) for a web depth of 0.5 m. The coal density is 1.4 tonne/m31.4\text{ tonne}/\text{m}^{3}. If the panel width is 150 m, the production per cycle in tonne is [rounded off to 1 decimal place]
GATE→2023→Mining Methods and Machinery→Mining Machinery
Q45
NAT[2 Marks]
Data related to a surface miner operation are given below: Drum width = 3.0 m, Average cutting depth = 20 cm, Average cutting speed = 25 m/min, Length of pit = 500 m, Turning time = 2 min, Truck exchange time = 30 s, Truck capacity = 15 m^3. Considering in situ volume, the production rate of the surface miner in m^3/hr, is [rounded off to 1 decimal place]
GATE→2023→Mining Methods and Machinery→Mining Methods
Q46
NAT[2 Marks]
A continuous miner served by two shuttle cars produces 240 tonne/hr240\text{ tonne/hr}. The capacity of each shuttle car is 10 tonne. When a single shuttle car operates, the cycle time becomes 4 min. In case one of the shuttle cars is under break-down, the reduction in hourly production from that of two cars in percent is [rounded off to 1 decimal place]
GATE→2023→Mining Methods and Machinery→Mining Machinery
Q47
NAT[2 Marks]
An unmanned aerial vehicle (UAV) with payload of 2 kg reaches vertically 100 m in 10 s at uniform velocity. The self-weight of the UAV is 1.2 kg. The power required in lifting in kW is [rounded off to 2 decimal places]
GATE→2023→Mining Methods and Machinery→Mining Methods
Q48
NAT[2 Marks]
A mine void of width 20 m, length 50 m and height 30 m is to be filled with mill tailings based cemented paste backfill (CPB). The CPB contains tailings:cement:water as 1.0:0.1:0.2 by weight. The specific gravity of tailings and cement are 2.8 and 2.4 respectively. Assuming 20% of the original volume of water is retained in the final backfill, the amount of cement in tonne required so as to fill the void completely is [rounded off to nearest integer]
GATE→2023→Mining Methods and Machinery→Mining Machinery
Q49
NAT[2 Marks]
Data related to a water turbine pump with backward bladed impellers are given below: Impeller diameter = 35 cm, RPM = 1200, Angle of curvature of blade = 30∘30^{\circ}, Radial velocity of discharge = 2 m/s2\text{ m/s}, Manometric efficiency = 0.8. The number of impellers required in the pump to lift water by a height 300 m is [rounded off to higher integer]

Surface Environment, Mine Ventilation and Underground Hazards

9 Questions
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Surface Environment
Q50
MCQ[1 Mark]
The reaction products of calcium hydroxide with acidic ferruginous mine water are
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Underground Hazards
Q51
MCQ[1 Mark]
An underground coal mine experienced 5 serious injuries, 15 reportable injuries, and 25 minor injuries during 2020. If the average employment in the mine is 1200, then the total injury rate per 1000 persons employed is
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Underground Hazards
Q52
MCQ[1 Mark]
As per DGMS guidelines, the risk score in Safety Management Plan for a hazard is computed as
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Mine Ventilation
Q53
NAT[1 Mark]
To increase the resistance of a mine roadway by 1.5 Ns2m−81.5\text{ Ns}^{2}\text{m}^{-8}, the size in m2\text{m}^{2} of the regulator to be installed is [rounded off to 2 decimal places]
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Underground Hazards
Q54
NAT[1 Mark]
In a panel with 50 workers, a miner typically consumes 2.5×10−3 m3/min2.5\times10^{-3}\text{ m}^{3}/\text{min} of oxygen. The percentage of oxygen in the intake air is 20.95%. To ensure minimum permissible oxygen in the return air as per CMR 2017 the quantity of ventilating air in m3/min\text{m}^{3}/\text{min} to be supplied to the panel is [rounded off to 2 decimal places]
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Mine Ventilation
Q55
MCQ[2 Marks]
A duct of diameter 0.60 m with an exhausting fan has -97.5 mm wg static pressure behind the fan when the air flow rate is 4.0 m3/s4.0\text{ m}^{3}/\text{s}. If an evasee with inlet to outlet area ratio of 1:4 and efficiency 60% is attached to the outlet of the fan, the static pressure of the fan in mm of wg becomes
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Surface Environment
Q56
NAT[2 Marks]
In a sample of groundwater, the concentration of Ca2+Ca^{2+} is 200 mg/l200\text{ mg/l}. The corresponding calcium carbonate hardness in mg/l\text{mg/l} is [rounded off to 1 decimal place]
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Surface Environment
Q57
NAT[2 Marks]
A thermal power station receives coal of calorific value 4000 kcal/kg4000\text{ kcal/kg} and uses 7000 tonnes of coal every day. Assuming 860 kcal is the heat equivalent of 1.0 kWh1.0\text{ kWh}, for a thermal efficiency of 40% and electrical efficiency of 85% the power generation per day in MWh is [rounded off to 1 decimal place]
GATE→2023→Surface Environment, Mine Ventilation and Underground Hazards→Mine Ventilation
Q58
NAT[2 Marks]
A fan installed in a mine ventilation system circulates 30 m3/s30\text{ m}^{3}/\text{s} of air to two districts A and B as shown in Figure below. It is desired to increase the quantity of air by 20% in the district B using a booster fan in it. Assuming that the main fan pressure is unchanged, the pressure of the booster fan, in Pa, is [rounded off to 2 decimal places]
Figure for Question 58

Mineral Economics, Mine Planning, Systems Engineering

7 Questions
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Systems Engineering
Q59
MCQ[1 Mark]
A linear programming problem is given as: Maximize Z=4x1+2x2Z=4x_{1}+2x_{2} Subject to: 2x1−2x2≤202x_{1}-2x_{2}\le20, 4x1≤804x_{1}\le80, x1≥0x_{1}\ge0, x2≥0x_{2}\ge0. The problem has
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Systems Engineering
Q60
MCQ[1 Mark]
In project scheduling techniques, the CORRECT statement is
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Mineral Economics
Q61
NAT[1 Mark]
The average ore grade of a copper deposit is 0.9%. The recovery of the metal after processing, smelting and refining is 85%. If the selling price of refined copper is Rs 640/kg640/kg, the sale value in Rs. from mining one tonne of ore is [rounded off to 1 decimal place]
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Systems Engineering
Q62
NAT[2 Marks]
The reliability function of a pump is given as R(t)=exp[−(t1000)0.5]R(t)=exp[-(\frac{t}{1000})^{0.5}] where t stands for time in years. If the pump comes with a six-month warranty, the number of years for the pump to attain a reliability of 0.9 is [rounded off to 2 decimal places]
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Systems Engineering
Q63
NAT[2 Marks]
A coal company has three mines which transport coal to four washeries. The daily production from each mine, the demand at each washery and unit transportation cost from each mine to each washery are given in table... The cost of initial basic feasible solution using Vogel's approximation method is [rounded off to 1 decimal place]
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Systems Engineering
Q64
NAT[2 Marks]
A workshop has four tasks and equal number of machines to perform the tasks. Each of the machines can perform only one of the four tasks. The estimated cost at each of the machines to complete each task is given in table... The total cost of optimal assignment is [rounded off to 1 decimal place]
GATE→2023→Mineral Economics, Mine Planning, Systems Engineering→Mineral Economics
Q65
NAT[2 Marks]
A mining company makes an initial investment of Rs 200 crore on a project. The following data are available: Production life: 3 years; Year wise production after gestation period (Mtonne): 1.0, 2.0, and 1.0; Stripping ratio: 1.5 m3/tonne1.5\text{ m}^{3}/\text{tonne}; Selling price of ore: Rs. 2000 per tonne; Ore mining cost: Rs. 500 per tonne; Waste mining cost: Rs. 500 per m3\text{m}^{3}; Discount rate: 10%. By ignoring any other cash-flows, if the NPV of the project becomes Rs. 5.367 crore, the gestation period of the project, in years, is [rounded off to the nearest integer]