WRD Maharashtra JE flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Modular ratio m

Ratio of modulus of elasticity of steel to that of concrete, m = E_s/E_c = 280/(3σ_cbc) in WSM; used to transform steel area into equivalent concrete area for composite section analysis.

Balanced section x_u/d

Depth of neutral axis ratio at which concrete and steel reach permissible limits simultaneously; IS 456 limits it to 0.53 for Fe250, 0.48 for Fe415 and 0.46 for Fe500.

Terzaghi strip footing equation

Ultimate bearing capacity q_u = cN_c + γD_f N_q + 0.5γBN_γ for a strip footing; N factors depend on the angle of internal friction φ.

Standard Proctor compaction

Laboratory test using 2.5 kg rammer with 310 mm drop, 25 blows per layer in 3 layers, giving compactive energy about 594 kJ/m³; determines OMC and maximum dry density.

Target mean strength

Design strength f_ck' = f_ck + 1.65s, where s is the assumed standard deviation; used in IS 10262 mix design to ensure the specified characteristic strength is achieved.

One-way slab span/depth

IS 456 basic span-to-effective-depth ratios: 20 simply supported, 26 continuous, 7 cantilever; multiplied by a modification factor depending on the tension steel percentage.

Minimum shear reinforcement

Requirement A_sv/(b·s_v) ≥ 0.4/(0.87f_y); maximum stirrup spacing is the lesser of 0.75d and 300 mm, ensuring ductile shear behaviour.

Lever arm in WSM

Distance between compressive and tensile resultants, z = jd with j = 1 − k/3; moment of resistance M = σ_st·A_st·z for a singly reinforced section.

Otto cycle efficiency

Air-standard efficiency η = 1 − 1/r^(γ−1), where r is the compression ratio and γ the specific heat ratio; efficiency rises with compression ratio.

Carnot COP

Coefficient of performance of a reversible refrigerator between cold reservoir T_L and hot reservoir T_H: COP = T_L/(T_H − T_L), with temperatures in kelvin.

Three-phase power formula

P = √3 V_L I_L cos φ for a balanced three-phase load; in star V_L = √3V_ph, in delta I_L = √3I_ph.

Transformer EMF equation

EMF per turn E_t = 4.44 f Φ_m; the ratio V_1/V_2 = N_1/N_2 = I_2/I_1 holds for an ideal transformer.

Induction motor slip

Slip s = (N_s − N_r)/N_s where N_s = 120f/P; rotor frequency equals s·f, and slip is 1 at standstill.

DC motor back EMF

For a DC motor, E_b = V − I_a R_a with E_b = (PΦNZ)/(60A); back EMF opposes the supply voltage and limits armature current.

Turbine specific speed

N_s = N√P/H^(5/4), used to select turbine type: Pelton for high head, Francis for medium head, Kaplan for low head and large discharge.

Belt velocity ratio

Ratio of pulley speeds equals ratio of diameters (plus belt thickness for crossed belts); slip reduces the actual ratio below the ideal value.

Kennedy's critical velocity

V_0 = 0.55 m·y^0.64, the non-silting and non-scouring velocity in an unlined canal; regime condition requires the actual velocity to equal V_0.

Lacey regime equations

P = 4.75√Q, V = (Qf²/140)^(1/6) with silt factor f = 1.76√d_mm; used to design stable unlined channels in alluvium.

Manning's equation

V = (1/n)R^(2/3)S^(1/2); n is roughness coefficient, R hydraulic radius and S bed slope; widely used for lined canal and channel design.

Duty and delta

Duty D (ha/cumec) = 8.64B/Δ and delta Δ (m) = 8.64B/D, where B is the base period in days; delta is depth of water required over the crop period.

Aqueduct vs superpassage

An aqueduct carries the canal over a drain; a superpassage carries the drain over the canal; selection depends on relative bed levels and the drain's high flood level.

Dam hazard classification

Dams are classed by hazard potential (high, significant, low) based on likely downstream consequences; class determines inspection frequency and emergency action plan requirements.

Reservoir routing continuity

I − O = dS/dt expresses storage change in a reservoir; combined with storage-elevation and elevation-discharge curves it gives outflow for a given inflow flood.

Duty of canal water

Area irrigated per unit discharge, usually hectares per cumec; it decreases with higher delta and longer base period and is used to fix canal design discharge.

Maharashtra formation date

Maharashtra was formed on 1 May 1960 under the Bombay Reorganisation Act, 1960, by splitting the bilingual Bombay State into Maharashtra and Gujarat.

Vidhan Parishad seats

The Maharashtra Legislative Council has 78 seats; one-third of members retire every two years, with members drawn from graduates, teachers, local bodies and the Governor's nominees.

Maharashtra divisions

Maharashtra has 36 districts grouped into 6 revenue divisions: Konkan, Nashik, Pune, Chhatrapati Sambhajinagar, Amravati and Nagpur.

Zilla Parishad Act, 1961

The Maharashtra Zilla Parishads and Panchayat Samitis Act, 1961 governs district-level and block-level rural local bodies; the Village Panchayats Act, 1959 governs Gram Panchayats.

Marathi vibhakti count

Marathi has 8 cases (विभक्ती) and 3 genders; case markers include -ने for कर्ता, -ला/-स for कर्म and -चा/-ची/-चे for षष्ठी.

Right to Public Services Act

The Maharashtra Right to Public Services Act, 2015 makes notified public services time-bound, with a first appeal to a designated officer and a second appeal to the appellate authority.

Water Resources Department

जलसंपदा विभाग, headed by the Minister and administered by the Secretary, plans and maintains irrigation projects, dams and canals; field units are headed by Chief and Executive Engineers.

Kalsubai peak

Kalsubai (1,646 m) in the Western Ghats of Nashik district is the highest point in Maharashtra; the Sahyadri range runs north-south along the state's western edge.