GATE Exam Questions Questions

• Direct shear test on cohesionless soil (c = 0) — find angle of internal friction φ (Given σ_n = 200 kN/m^2; failure shear stress τ_f = 100 kN/m^2.)
• Fluid dynamics — where do both Reynolds and Froude numbers matter? In which of the following real-world flows are both viscous/inertial effects (Reynolds number) and gravity/free-surface wave effects (Froude number) simultaneously significant for modelling and performance assessment?
• Dimensional analysis — choosing repeating variables correctly When applying the Buckingham Π method, how should the set of repeating variables be chosen?
• Bernoulli application — pressure difference ahead of a moving body A body moves through still water at 6 m/s. At a point 1 m ahead of the body, the local water speed is measured as 4 m/s. Estimate the pressure difference p_nose − p_ahead between the stagnation point at the nose and the point 1 m ahead (assume incompressible, same elevation, negligible losses; ρ ≈ 1000 kg/m^3).
• Hydraulic jump in a rectangular channel — governing equations used When deriving the relationship between conjugate depths and the initial Froude number for a hydraulic jump in a horizontal rectangular channel, which fundamental equations are used?
• Soil classification — use of particle size distribution (gradation) curves For which materials are particle size distribution curves particularly useful for classification and engineering description?
• Highway design — definition of stopping sight distance (SSD) Stopping sight distance on a highway is defined as the minimum length of roadway visible ahead to:
• Hydrology instrument — what does a lysimeter measure? A lysimeter is primarily used to measure which hydrologic quantity for a vegetated plot under controlled conditions?
• Flexible pavements — probable cause of rutting Which of the following is a common and probable cause of rutting (permanent longitudinal depressions) in flexible pavements?
• Irrotational flow — the mathematical condition in 2D For a two-dimensional velocity field with components u(x,y) and v(x,y), which relation must hold everywhere for the flow to be irrotational?
• Water chemistry – computing pH from hydroxide ion concentration at 25 °C A wastewater sample contains [OH⁻] = 10^(-5.6) mmol/L at 25 °C. Calculate the pH of the sample. (Assume pure-water ionic product Kw = 1.0 × 10^(-14) at 25 °C and carefully convert units from mmol/L to mol/L.)
• Pile foundations – understanding pile group efficiency The efficiency of a pile group (ratio of group capacity to the sum of individual pile capacities) depends on spacing, layout, and soil behavior. Which statement best reflects reality across soils and arrangements?
• Steel roof trusses – effective length of a rafter between nodes for out-of-plane buckling A rafter member has lateral restraints (nodes) at a spacing of L measured perpendicular to the truss plane. Assuming simple (pin-like) restraint at nodes out of plane, the effective length for out-of-plane buckling should be taken as:
• Irrigation design – compute depth of water (Δ) from duty and base period Given duty D = 1428 hectares per cumec and base period B = 120 days for a crop, determine the required depth of water Δ in metres (use the standard relation with consistent units).
• Axially loaded pile in clay – compute skin friction capacity A single pile of diameter 0.50 m and length 10 m is embedded in saturated clay. Undrained strength parameters: cohesion cu = 60 kN/m², angle of internal friction φ = 0. Adhesion factor α = 0.6. Assuming only shaft resistance in undrained conditions, compute the skin friction capacity (in kN).
• Air pollution basics – identify primary pollutants Primary pollutants are emitted directly from sources, whereas secondary pollutants form in the atmosphere. Which pair lists two primary air pollutants?
• Flood routing – Muskingum method classification The Muskingum method is widely used in hydrology. Which statement best describes its nature and application?
• Shear centre – definition of the special load application point In an open thin-walled section, the shear centre is the unique point through which if the resultant transverse load acts, the member will experience no:
• Rankine active earth pressure – total thrust on a dry sand backfill A vertical retaining wall of height H = 3 m retains a horizontal backfill of dry sand with unit weight γt = 20 kN/m³ and angle of shearing resistance φ' = 30°. The groundwater table is at the base (i.e., the backfill above is dry). Compute the total active thrust per metre length on the wall.
• Wastewater Treatment – 5-Day BOD vs Ultimate BOD (at 20 °C) In standard wastewater analysis, what percentage of the ultimate biochemical oxygen demand (BODu) is typically exerted in the standard 5-day BOD test (BOD5) conducted at 20 °C?