Viscosity With Exams Based MCQ IMP for GATE , SSC JE , PSU

Viscosity : It is the property of the fluid  which opposes the relative motion between the two surfaces of the fluid in a fluid that are moving a different velocity.

Viscosity can be two types:

1: Dynamic Viscosity Or Absolute Viscosity Or Coefficient of Viscosity or Viscosity

2: Kinematic Viscosity ( This is imaginary not really present in real life)

The main difference between Dynamic viscosity and Kinematic Viscosity is:

Dynamic Viscosity: One way is to measure a fluid's resistance to flow when an external force is applied , This is Dynamic viscosity , always it is used for practical purpose.


Units: SI : N.S/ m2

C.G.S Unit: Dyne-Sec/ Cm2 ( It is also called Poise)

M.K.S. Unit: Kgf-Sec/ m2


Kinematic Viscosity: The other way is to measure the resistive flow of a fluid under the weight of gravity , the result is kinematic vicosity . Do not use it by your own, until  there is no mention of particulate word (Kinematic Viscosity) in numerical .

Units:  SI : m2/s

CGS unit: cm2/sec ( It is called stoke )

M.K.S =m2/Sec

IMP Point:-

Two fluid that have the same Dynamic viscosity can have different kinematic viscosity  This is due to kinematic viscosity dependent on the density of the fluid , density is not a factor with Dynamic viscosity .

Some Other Key Points regarding Viscosity:


1: The dynamic viscosity of pure water at 20 degree Celsius is 0.01 poise or 1 centi poise

2: The viscosity of fluid decreases with increasing the temperature ( Because fluid has a tendency to flow in stream line in most of the cases , when velocity of flow is low)

3: The viscosity of gases increases with increasing the temperature ( REASON:  when we heat the gases then gas molecules travel in zig zag motion, so the momentum of gases particles increases and they generate high shear stress due to high momentum)

4: Water has higher viscosity than Mercury.

 Now test youself  : MCQ :  based on Viscosity:

Q1: Poise is the C.G.S unit of:
A: Viscosity
B: Kinematic Viscosity
C: Surface Tension
D: Capillary


 Q2: C.G.S unit of Kinematic Viscosity is:
A: Newton-Sec
B: Stoke 
C: Dyne
D: Poise

Q3: The increase of the temperature :
A: Increase the viscosity of liquid
B Increase the viscosity of gases 
C: Decrease the viscosity of gases
D: No effect


 Q4: Newton law of viscosity states that :

A: shear stress is directly proportional to the velocity
B: Shear stress is directly proportional to velocity
C: shear stress is directly proportional to rate of shear strain
D: Shear stress is directly proportional to the viscosity

Q5: Which has higher viscosity : A : Mercury, B: Water  

Q6:  What measures a material's resistance to flow?
  


A: Matter , B: Volume C: Viscosity, D: Surface Tension
Q7: When friction increases what else increases?                                                                                        A: Elasticity , B: Density , C: Viscosity, D: Matter


 







                                                                                

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Interviews and Exams questions : ALL About Cement

1: Name the component that responsible for early strength of concrete:

Ans: C3S ( Tri Calcium silicate ) , that react with water and produces more heat of hydration is responsible for early strength of concrete.

2: Which compound contribute to the later strength of concrete ?

Ans: C2S ( Di Calcium silicate ) that hydrates slowly , contribute to the later strength of concrete .

3: After how many days , the compressive strength developed by C3S and C2S are equal .

Ans: ONE year  

4:For road rapid work which type of cement is recommended :

Ans: Rapid hardening cement

5: In how many  days , about 50% of the total heat evolution occurs.

Ans: During the first 3 days of hydration 

6:Which oxides are responsible for high early strength of cement ?

Ans: High total alumina and high ferric oxide content favour the production of high early strength in cement

Compounds : When components of cements added up with water than they called compound in simple language ..

Tricalcium Silicate (C3S) hardens rapidly and is largely responsible for initial set and early strength.

In general, the early strength of portland cement concrete is higher with increased percentages of C3S.

Dicalcium Silicate (C2S) hardens slowly and contributes largely to strength increases at ages beyond 7 days.

Tricalcium Aluminate (C3A) liberates a large amount of heat during the first few days of hardening and, together with C3S and C2S may somewhat increase the early strength of the hardening cement (this effect being due to the considerable heat of hydration that this compound evolves). It does affect set times.

Tetracalcium Aluminoferrite (C4AF) contributes very slightly to strength gain. However, acts as a flux during manufacturing. Contributes to the color effects that makes cement gray.aakes cement gray.

Compounds by percentage :

Role of compounds on properties of cement : MOST IMP

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Syllabus for Civil Engineering (CE) == >

GATE 2015 paper Pattern for Civil Engineering
Engineering Mathematics	Engineering Mathematics will have 13% of total marks weigh
General Aptitude	General Aptitude will have 15% of total marks weigh
Subject questions	Subject questions will have rest 72% of total marks weigh

           Syllabus for Civil Engineering (CE)  == >

ENGINEERING MATHEMATICS = =>

Linear Algebra: Matrix algebra, Systems of linear equations, Eigen values and eigenvectors. 

Calculus: Functions of single variable, Limit, continuity and differentiability, Mean value 

theorems, Evaluation of definite and improper integrals, Partial derivatives, Total derivative, 

Maxima and minima, Gradient, Divergence and Curl, Vector identities, Directional derivatives, 

Line, Surface and Volume integrals, Stokes, Gauss and Green’s theorems. 

Differential equations: First order equations (linear and nonlinear), Higher order linear 

differential equations with constant coefficients, Cauchy’s and Euler’s equations, Initial and 

boundary value problems, Laplace transforms, Solutions of one dimensional heat and wave 

equations and Laplace equation. 

Complex variables: Analytic functions, Cauchy’s integral theorem, Taylor and Laurent series. 

Probability and Statistics: Definitions of probability and sampling theorems, Conditional 

probability, Mean, median, mode and standard deviation, Random variables, Poisson, Normal 

and Binomial distributions. 

Numerical Methods: Numerical solutions of linear and non-linear algebraic equations 

Integration by trapezoidal and Simpson’s rule, single and multi-step methods for differential 

equations. 

STRUCTURAL ENGINEERING = =>

Mechanics: == >

Bending moment and shear force in statically determinate beams. Simple stress and 

strain relationship: Stress and strain in two dimensions, principal stresses, stress transformation, 

Mohr’s circle. Simple bending theory, flexural and shear stresses, unsymmetrical bending, shear 

centre. Thin walled pressure vessels, uniform torsion, buckling of column, combined and direct 

bending stresses. 

Structural Analysis: = =>

Analysis of statically determinate trusses, arches, beams, cables and 

frames, displacements in statically determinate structures and analysis of statically indeterminate 

structures by force/ energy methods, analysis by displacement methods (slope deflection and 

moment distribution methods), influence lines for determinate and indeterminate structures. 

Basic concepts of matrix methods of structural analysis. 

Concrete Structures == >

 Concrete Technology- properties of concrete, basics of mix design. 

Concrete design- basic working stress and limit state design concepts, analysis of ultimate load 

capacity and design of members subjected to flexure, shear, compression and torsion by limit 

state methods. Basic elements of prestressed concrete, analysis of beam sections at transfer and 

service loads. Steel Structures: Analysis and design of tension and compression members, beams and beam- 

columns, column bases. Connections- simple and eccentric, beam–column connections, plate 

girders and trusses. Plastic analysis of beams and frames. 

GEOTECHNICAL ENGINEERING = =>

Soil Mechanics: == >

Origin of soils, soil classification, three-phase system, fundamental definitions, 

relationship and interrelationships, permeability &seepage, effective stress principle, 

consolidation, compaction, shear strength. 

Foundation Engineering:  == >

Sub-surface investigations- scope, drilling bore holes, sampling, 

penetration tests, plate load test. Earth pressure theories, effect of water table, layered soils. 

Stability of slopes-infinite slopes, finite slopes. Foundation types-foundation design 

requirements. Shallow foundations-bearing capacity, effect of shape, water table and other 

factors, stress distribution, settlement analysis in sands & clays. Deep foundations–pile types, 

dynamic & static formulae, load capacity of piles in sands & clays, negative skin friction. 

WATER RESOURCES ENGINEERING  = =>

Fluid Mechanics and Hydraulics:= = = > 

Properties of fluids, principle of conservation of mass, 

momentum, energy and corresponding equations, potential flow, applications of momentum and 

Bernoulli’s equation, laminar and turbulent flow, flow in pipes, pipe networks. Concept of 

boundary layer and its growth. Uniform flow, critical flow and gradually varied flow in channels, 

specific energy concept, hydraulic jump. Forces on immersed bodies, flow measurements in 

channels, tanks and pipes. Dimensional analysis and hydraulic modeling. Kinematics of flow, 

velocity triangles and specific speed of pumps and turbines. 

Hydrology: == >

Hydrologic cycle, rainfall, evaporation, infiltration, stage discharge relationships, 

unit hydrographs, flood estimation, reservoir capacity, reservoir and channel routing. Well 

hydraulics. 

Irrigation: == >

Duty, delta, estimation of evapo-transpiration. Crop water requirements. Design of: 

lined and unlined canals, waterways, head works, gravity dams and spillways. Design of weirs 

on permeable foundation. Types of irrigation system, irrigation methods. Water logging and 

drainage, sodic soils. 

ENVIRONMENTAL ENGINEERING  = =>

Water requirements:= = =>

Quality standards, basic unit processes and operations for water 

treatment. Drinking water standards, water requirements, basic unit operations and unit processes 

for surface water treatment, distribution of water. Sewage and sewerage treatment, quantity and 

characteristics of wastewater. Primary, secondary and tertiary treatment of wastewater, sludge 

disposal, effluent discharge standards. Domestic wastewater treatment, quantity of characteristics 

of domestic wastewater, primary and secondary treatment Unit operations and unit processes of 

domestic wastewater, sludge disposal. Air Pollution: Types of pollutants, their sources and impacts, air pollution meteorology, air 

pollution control, air quality standards and limits. 

Municipal Solid Wastes:= =>

 Characteristics, generation, collection and transportation of solid 

wastes, engineered systems for solid waste management (reuse/ recycle, energy recovery, 

treatment and disposal). 

Noise Pollution: Impacts of noise, permissible limits of noise pollution, measurement of noise 

and control of noise pollution. 

TRANSPORTATION ENGINEERING  = =>

Highway Planning: Geometric design of highways, testing and specifications of paving 

materials, design of flexible and rigid pavements. 

Traffic Engineering: Traffic characteristics, theory of traffic flow, intersection design, traffic 

signs and signal design, highway capacity. 

SURVEYING  = =>

Importance of surveying, principles and classifications, mapping concepts, coordinate system, 

map projections, measurements of distance and directions, leveling, theodolite traversing, plane 

table surveying, errors and adjustments, curves. 

 

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