NHPC-JE’21 CE: Daily Practices Quiz. 07-Oct-2021

Know your strengths and practice your concepts with this quiz on NHPC JE Recruitment 2021. This quiz for NHPC JE Recruitment 2021 is designed specially according to NHPC Syllabus 2021.

Quiz: Civil Engineering
Exam: NHPC-JE
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes

Q1. A vertical plate of a plate girder is called
(a) Web plate
(b) Flange plate
(c) Cover plate
(d) None of these

Q2. An aggregate is said to be flaky if its least dimension is less than …………….
(a) 1/5th of mean dimension
(b) 2/5th of mean dimension
(c) 3/5th of mean dimension
(d) 4/5th of mean dimension

Q3. A line joining some fixed points on the main survey lines, is called a
(a) Check line
(b) Tie line
(c) Base line
(d) None of these

Q4. In absence of detailed design, the percentage for steel concrete may be taken approximately for beams is
(a) 0.7% to 1.0%
(b) 1.0% to 2.0%
(c) 1.0% to 5.0%
(d) 0.5% to 0.8%

Q5. Which of the following method is not a direct stream flow measurement technique?
(a) Dilution method
(b) Ultrasonic method
(c) Area-velocity method
(d) Slope-area method

Q6. The type of cement used in lining of deep tube wells is:
(a) Blast furnace slag cement
(b) Portland pozzolana cement
(c) Oil well cement
(d) High alumina cement

Solutions

S1. Ans.(a)
Sol. A vertical plate of a plate girder is called web plate. The thickness and depth of web plate depends upon bending moment and shear stress acting on the plate.

S2. Ans.(c)
Sol. An aggregate is said to be flaky it the percentage of particle having their least size smaller than 3/5th of their mean dimension.

S3. Ans.(b)
Sol. Lines used in surveying →
Main line → These lines connect main stations also called survey line or chain line.
Check line → It is used to check the accuracy of work.
Base line → It is the biggest central line which divide the whole area into two parts.
Tie line → It is used for detailing of features or nearby objects in area and join some fixed points on the main survey line.

S4. Ans.(b)
Sol. In the absence of detailed design, the percentage of steel is taken as-
In case of raft foundation → 0.5% to 0.8%
In case of slab → 0.7% to 1.0%
In case of beam → 1.0% to 2.0%
In case of column → 1.0% to 5.0%

S5. Ans.(d)
Sol. Slope area method is not a direct stream flow measurement technique. This method is used for high water marks and wash lines. Manning’s equation is used in this method to calculate the discharge.
Q=1/n AR^(2/3) S^(1/2)
n= Meaning’s co-efficient
R= Hydraulic mean radius
S= side slope
A= Area

S6. Ans.(b)
Sol. Portland – Pozzolana cement (PPC) is used in lining of deep tube wells. It is manufactured by grinding OPC and Pozzolana (containing fly ash 10 to 25% by mass). It is also used in mass concreting and places of high temperature.

NHPC JE’21 ME: Daily Practices Quiz. 07-Oct-2021

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NHPC JE Recruitment 2021

National Hydroelectric Power Corporation (NHPC) has released the recruitment notification for engagement of following posts such as Senior Medical Officer, Assistant Rajbhasha Officer, Junior Engineer & Sr. Accountant posts. NHPC expects application from High Performing, Dynamic & Achievement-Oriented Professionals candidates to fill up these 173 vacancies.

NHPC-JE’21 ME: Daily Practices Quiz

NHPC-JE’21 ME: Daily Practices Quiz 07-Oct-2021

Quiz: Mechanical Engineering
Exam: NHPC JE
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 6 Minutes

Q1. The mechanism, which is an exact straight-line mechanism using lower pairs?
(a) Watt’s mechanism
(b) Grasshopper mechanism
(c) Robert’s mechanism
(d) Peaucellier’s mechanism

Q2. In a mechanism having 8 links, the number of instantaneous centres of rotation present are
(a) 28
(b) 56
(c) 15
(d) 0

Q3. The length of a flat plate is 2 m and width 50 cm is placed in a fluid stream at 50^o C blowing parallel to it. The convective heat transfer co-efficient of the fluid is 10 W/〖(m〗^2 K). The heat transfer takes place, if the plate is maintained at a temperature of 350^o C is
(a) 3 kW
(b) 4 kW
(c) 0.3 kW
(d) 30 kW

Q4. Resilience means
(a) Failure of material at loads less than at normal conditions
(b) Resilience of the material to elastic deformation
(c) Ability of the material to return to the original shape when load is removed.
(d) Capacity of a material to absorb energy elastically

Q5. Maximum shear stress theory was postulated by ___.
(a) St. Venant
(b) Mohr
(c) Rankine
(d) Tresca

Q6. Which of the following is TRUE for factor of safety?
(a) Tensile stress/permissible stress
(b) Compressive stress/Ultimate stress
(c) Ultimate stress/Permissible stress
(d) Ultimate stress/Shear stress

Solutions

S1. Ans. (d)
Sol. Peaucellier’s mechanism is an exact straight-line mechanism using lower pairs

S2. Ans. (a)
Sol. Center of rotation =C_2^8=(8×7)/2=28

S3. Ans(a)
Sol. by Newton’s law of cooling for convection heat transfer
Q=h A ∆T
Q=10×2×0.50×(350-50)
Q=3 kW

S4. Ans(d)
Sol.
Resilience – Capacity of a material to absorb energy elastically
Fatigue – Failure of material at loads less than at normal conditions
Stiffness – Resilience of the material to elastic deformation
Elasticity – Ability of the material to return to the original shape when load is removed.

S5. Ans.(d)
Sol. maximum shear stress theory also known as Guest & Tresca theory because it is postulated by Tresca.

S6. Ans.(c)
Sol. factor of safety is defined as the ratio of failure stress (i.e. ultimate stress) to the working stress (i.e. permissible stress)
FOS=(Ultimate stress)/(Permissible stress)

UPPSC Lec’21 ME: Daily Practices Quiz. 07-Oct-2021

Quiz: Mechanical Engineering
Exam: UPPSC Lecturer
Topic: SOM & FM

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 6 Minutes

Q1. In the design of singly reinforced simply supported beams, the maximum bending moment will be (Given W is the maximum load and “I” is the length):
(a) Wl/64
(b) W/8l²
(c) Wl^2 \/8
(d) W^2 \/32

Q2. What is the power (in kW) transmitted by a rotating shaft? (Where: P = power, N= Speed in rpm and T = Torque transmitted)
(a) 2πNT/60
(b) 2πNT²/60000
(c) NT/60000π
(d) 2πNT/60000

Q3. The angle of twist proportional to twisting moment.
(a) Directly
(b) Inversely
(c) Both (A) & (B)
(d) None of these

Q4. Discharge formula for triangular weir is:
(a) 8/15 Cd √2g H^(5/2)
(b) 8/15 Cd √2g H^(3/2)
(c) 8/15 Cd √2g H^(1/2)
(d) 8/15 Cd √2g H^

Q5. Pitot tube is used to measure………….
(a) Discharge
(b) Average velocity
(c) Velocity at a point
(d) Pressure at a point

Q6. Which one of the following is not a non-dimensional parameter?
(a) Froude number
(b) Mach number
(c) Chezy’s coefficient
(d) Darcy -Weisbach friction factor

Solutions

S1. Ans. (c)
Sol.

Sample Page - Part 350_2.1

S2. Ans. (d)
Sol. Power (P) = 2πNT/60 (watts)
P= 2πNT/60×1/10³ (Kilo watt)
P=2πNT/60000

S3. Ans. (a)
Sol. T/J=τ/R=Gθ/L
T α Q

S4. Ans. (a)
Sol. discharge for triangular notch (Q)
Q = 8/15 C_d √2g H^(5/2)

S5. Ans. (c)
Sol. Pitot tube is used to measure velocity at a point.
V=C_v √2gH
S6. Ans. (c)
Sol. (i) Fr = V/√gy = (m/sec)/(√(m/sec²) × m) = (m/sec)/(m/sec) = 1
(ii) Mach Number – (Ma) = V/√(k/ρ)
= (m/sec)/(√(N/m^2 ) × m³/kg) = (m/sec)/(√((kg.m)/(sec^2×m²)) ×m³/kg) = 1
(iii) chezy’s coefficient (c) = √(8g/f)
= √(m/sec²)

= [L^(1/2) T^(-1)]

Daily Concept Booster Mechanical Engineering: Principal Stress

Table of Contents

Principal Stress

Principal stress is the maximum or minimum normal stress.
The plane of principal stress has zero shear stress.

Sign Conventions

Tensile stress is positive and compressive stress is negative in nature.
Angle ‘θ’ is considered positive if it is in anti – clockwise direction.
Shear stress acting on a positive face of an element is considered positive if it acts in positive direction of one of the co-ordinate axes and negative if acts in the negative direction of the axes. Similarly on a negative face of an element is positive if act in negative direction of the axes and negative if it acts in the positive direction.

Maximum stress and Minimum stress

Let σ_1 and σ_2 are given principal stress, then normal and shear stress on any plane which is inclined at angle ‘θ’ from maximum principal plane (σ_1 > σ_2)

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UPPSC-LECTURER’21 EE: Daily Practices Quiz 05-Oct-2021

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UPPSC Technical Education Teaching Exam Notification 2021

Uttar Pradesh Public Service Commission has released the official notification for the recruitment of Principal, Lecturer, Librarian, and Workshop Superintendent. The Online application has been started on 15th September 2021 and the last date to apply online is 15th October 2021. The recruitment is for a total of 1370 UPPSC Polytechnic Lecturer Vacancies.

UPPSC-LECTURER’21 EE: Daily Practices Quiz

UPPSC-LECTURER’21 EE: Daily Practices Quiz 05-Oct-2021

Each question carries 3 marks.
Negative marking: 1 mark each or 1/3rd
Total Questions: 06
Time: 08 min.

Q1. Which of the following is a non-maskable interrupt of 8085 microprocessors?
(a) INTR
(b) TRAP
(c) RST 6.5
(d) RST 7.5

Q2. A 1:5 step-up transformer has 120 V across the primary and 600 Ω resistance across the secondary. Assuming, 100 % efficiency, the primary current equals…
(a) 5 A
(b) 10 A
(c) 20 A
(d) 0.2 A

Q3. A bipolar transistor has α=0.98, ICO=10 µA. If the base current is 100 µA, then collector current would be
(a) 4.9 mA
(b) 2.9 mA
(c) 3.4 mA
(d) 5.4 mA

Q4. What are the average and RMS values of half wave rectified output if peak voltage is 5 V?
(a) 1.59 V, 2.5 V
(b) 3.18 V, 2.5 V
(c) 1.59 V, 5 V
(d) 3.18 V, 5 V

Q5. What is the value of charging current in short transmission lines?
(a) Less than medium transmission lines
(b) Equal to medium transmission lines
(c) More than medium transmission lines
(d) More than long transmission lines

Sample Page - Part 350_5.1

SOLUTIONS

S1. Ans.(b)
Sol. The hardware vectored interrupts are classified in to maskable and non-maskable interrupts.
TRAP is non-maskable interrupt.
RST 7.5, RST 6.5, RST 5.5 and INTR are maskable interrupt.

S2. Ans.(a)
Sol. K=5
R1=600/K^2 =600/25=24 Ω
∴I1=V1/R1 =120/24=5 A

S3. Ans.(d)
Sol. α=0.98 (given)
∴current gain factor(β)=α/(1-α)=0.98/(1-0.98)=49
∴IC=βIB+(1+β) ICO=49×100×10^(-6)+(1+49)×10×10^(-6)=5.4 mA

S4. Ans.(a)
Sol. For half-wave rectifier: Vavg=Vm/π=5/3.14=1.59 V
And Vrms=Vm/2=5/2=2.5 V

S5. Ans.(a)
Sol. Line to Earth capacitance of short transmission line is less than that in medium and long transmission line and is negligible. Because of this the charging current of short transmission line is less than that in medium and long transmission line and is negligible.

Sample Page - Part 350_6.1

Daily Concept Booster Civil Engineering : Strain in different direction

Strain in different direction

σx,σy&σz→ Stress in x, y & z direction’s
ϵx,ϵy&ϵz→ Strain in x, y & z direction’s
μ → Poisson ratio
(ϵx=σx/E-μ σy/E-μ σz/E)
(ϵy=σy/E-μ σz/E-μ σx/E)
(ϵz=σz/E-μ σx/E-μ σy/E)

UPSSSC-JE’21 CE: Daily Practice Quiz. 05-October-2021

Know your strengths and practice your concepts with this quiz on UPSSSC-JE Recruitment 2021. This quiz for UPSSSC-JE Recruitment 2021 is designed specially according to UPSSSC-JE Syllabus 2021.

Quiz: Civil Engineering
Exam: UPSSSC-JE
Topic: MISCELLANEOUS

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes

Q1. When H is the flight height, R is the appropriate radial measure and d is the relief displacement the vertical height of an object appearing on an aerial photograph is
(a) dH/R
(b) R/dH
(c) RH/d
(d) H/dR

Q2. A rainfall with an intensity of 5 mm/hr is classified as
(a) Trace
(b) Light rain
(c) Moderate rain
(d) Heavy rain

Q3. Which of the following equations is used in hydrologic flood routing method?
(a) Lacey’s equation
(b) Equation of motion
(c) Energy equation
(d) Continuity equation

Q4. In a linear reservoir :
(a) outflow rate varies linearly with storage
(b) volume varies with elevation
(c) storage varies linearly with time
(d) storage varies linearly with inflow rate

Q5. Chlorine usage in the treatment of 25000 m³/day of water has been 9 kg/day. The residual chlorine after 10 minutes contact is 0.2 mg/l. The chlorine demand of water would be nearly
(a) 0.12 mg/l
(b) 0.16 mg/l
(c) 0.22 mg/l
(d) 0.28 mg/l

Q6. The unit in which both sedimentation and digestion processes of sludge take place simultaneously is called:
(a) Skimming tank
(b) Detritus tank
(c) Imhoff tank
(d) Digestion tank

SOLUTION

S1. Ans.(a)
Sol. Relief displacement is given as-
▭(d=Rh/H)
Vertical height ▭((h)=dH/R)
Where d = relief displacement
H = flying height
R = Radial distance

S2. Ans.(c)
Sol.

Intensity of Rainfall	Rain type
0-2.5 mm/Hr.	Light Rain
2.5-7.5 mm/Hr.	Moderate rain
>7.5 mm/Hr.	Heavy rain

S3. Ans.(d)
Sol. In hydrologic flood routing, continuity equation is used.
Q=A_1 V_1=A_2 V_2

S4. Ans.(a)
Sol. in a linear reservoir, outflow rate varies linearly with storage.

S5. Ans.(b)
Sol. Given,
Quantity of water treated = 25000 m³/day
Chlorine use = 9 kg/day
Chlorine dose = (Chlorine used)/(Quantity of water treated)
=(9 kg/day)/(25000 m^3/day)
=(9×10^6 mg/day)/(25000×10^3 l/day)
= 0.36 mg/l
Chlorine demand = Chlorine dose – Residual chlorine
= 0.36 – 0.2
= 0.16 mg/l

S6. Ans.(c)
Sol. An Imhoff tank is an improvement over septic tank in which both sedimentation and digestion process of sludge takes place.

NHPC-JE’21 CE: Daily Practices Quiz. 06-Oct-2021

Know your strengths and practice your concepts with this quiz on NHPC JE Recruitment 2021. This quiz for NHPC JE Recruitment 2021 is designed specially according to NHPC Syllabus 2021.

Quiz: Civil Engineering
Exam: NHPC-JE
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes

Q1. In an under-reinforced section, the value of actual neutral axis xa and the critical neutral axis xc are related as:
(a) x_a=x_c
(b) x_a>x_c
(c) x_a>2x_c
(d) x_a<x_c

Q2. Reusable wastewater from residential, commercial and industrial bathroom sinks, bath tub shower drains and clothes washing equipment drains, is known as
(a) Blue water
(b) Black water
(c) Brown water
(d) Grey water

Q3. Crushing strength of a good building stone should be more than:
(a) 50 MPa
(b) 150 MPa
(c) 100 MPa
(d) 200 MPa

Q4. The fore bearing of a line is 145°30’. What is its back bearing?
(a) 34°30’
(b) 325°60’
(c) 325°30’
(d) 324°30’

Q5. The total length of bar having hook at both the ends is:
(a) L + 9D
(b) L + 24D
(c) L + 18D
(d) L + 12D

Q6. The absolute minimum radius of curve for safe operation, for a speed of 100 kmph is:
(a) 260 m
(b) 440 m
(c) 360 m
(d) 320 m

Solutions

S1. Ans.(d)
Sol. Actual neutral axis = x_a
critical neutral axis = x_c
x_a<x_c→ under reinforced
x_a=x_c→ Balance section
x_a>x_c→ Over reinforced

S2. Ans.(d)
Sol. Reusable wastewater from residential, commercial and industrial bathroom sinks, bath tub shower drains and clothes washing equipment drains, is known as grey water.

S3. Ans.(c)
Sol.
– Crushing strength of a good building stone should be more than 100 MPa or 1000 kg/cm².
– Crushing test is performed to determine crushing strength.

S4. Ans.(c)
Sol. F.B = 145°30’
B.B = ?
F.B < 180°, hence
B.B = F.B + 180°
= 145°30’ + 180°
= 325° 30’

S5. Ans.(c)
Sol. The total length of bar having hook at both the ends is L + 18D.
Where L = length of bar
D = Diameter of bar.

S6. Ans.(c)
Sol. Given,
Minimum design speed V_min = 100 kmph
e_max = 0.07, f = 0.15 (Normally)
Absolute minimum radius (R_Absolute)→
R_Absolute=V^2/127(e+f)
=(100)^2/127(0.07+0.15)
= 357.9 m ≃ 360 m

UPPSC Lec’21 ME: Daily Practices Quiz. 06-Oct-2021

Quiz: Mechanical Engineering
Exam: UPPSC Lecturer
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 6 Minutes

Q1. Which of the following is incorrect for NC machine tool?
(a) Instruction undergoes electronic processing and outcome is the pulsed command
(b) Control unit sends signals to drive unit of machine tool and to magnetic box
(c) Instruction for manufacturing the components is written in coded language and read by tape recorder
(d) All of the above

Q2. The system which is not the actuation system of NC machine tool?
(a) Contour system
(b) Pneumatic system
(c) Electromechanical system
(d) Hydraulic system

Q3. Otto cycle consists of
(a) Two constant volume & two isentropic processes
(b) Two isothermal and two isentropic processes
(c) Two constant pressure and two isentropic processes
(d) One constant volume, one constant pressure and two isentropic processes

Q4. Perpetual motion machine of second kind (PMM-I) violates the
(a) Zeroth law of thermodynamics
(b) First law of thermodynamics
(c) Second law of thermodynamics
(d) Third law of thermodynamics

Q5. If the radius is doubled and the speed is reduced to half of its original value, the centrifugal force would be:
(a) 2.0 times the original value
(b) 0.5 times the original value
(c) 0.2 times the original value
(d) 0.1 times the original value

Q6. As compared to the mass of a body on the earth, its mass on the moon will be
(a) 6 times higher
(b) 6 times lower
(c) √6 times higher
(d) None of these

Solutions

S1. Ans. (d)
Sol. All of the above statements are correct.

S2. Ans. (a)
Sol. Contour system is not the actuation system of NC machine tool.

S3. Ans. (a)
Sol. Carnot cycle consists of two isothermal and two isentropic processes.
Otto cycle consists of two constant volume and two isentropic processes.

S4. Ans. (b)
Sol. Perpetual motion machine of second kind (PMM-II) violates the second law of thermodynamics.
Perpetual motion machine of second kind (PMM-I) violates the first law of thermodynamics.

S5. Ans. (b)
Sol.
F_2/F_1 =m_2/m_1 ×(ω_2/ω_1 )^2×r_2/r_1
=(1/2)^2×2=2/4=0.5 (∵ m_1=m_2)

S6. Ans. (d)
Sol. On moon only acceleration due to gravity is one sixth of acceleration due to gravity on earth.
g^’=g/6
So, weight of the body on moon becomes one sixth of the weight of the body on earth.
But there is no change in mass.

NHPC JE’21 ME: Daily Practices Quiz. 06-Oct-2021

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NHPC JE Recruitment 2021

NHPC-JE’21 ME: Daily Practices Quiz

NHPC-JE’21 ME: Daily Practices Quiz 06-Oct-2021

Quiz: Mechanical Engineering
Exam: NHPC JE
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 6 Minutes

Q1. The dimension of kinetic energy correction factor α is
(a) M^0 LT^0
(b) M^0 L^1 T^(-2)
(c) M^0 L^0 T^0
(d) M^1 L^2 T^(-2)

Q2. At critical depth of flow
(a) The Froud’s number has a unit value
(b) The specific energy is maximum for a given discharge
(c) The discharge is minimum
(d) The discharge is maximum

Q3. In casting, while designing Gating system, the formula of choke is (A) is
where, m = mass of casting, ρ = density of molten metal, H = effective metal height, ɳ = efficiency factor, t = pouring time
(a) A=m/(ρtɳ √2gH)
(b) A=mρt/(ɳ √2gH)
(c) A=2m/(ρtɳ √2gH)
(d) A=(mtɳ )/(ρ√2gH)

Q4. Which of the following is (are) the casting defect?
(a) Hot spot
(b) Blow holes
(c) Fusion
(d) All of these

Q5. The moment of inertia of a hollow circular section whose external diameter is 13 cm and internal diameter is 12 cm about centroidal axis is _______
(a) 437.5
(b) 137.5
(c) 284.5
(d) 384.1

Q6. Which cross-section of a cantilever beam which is loaded with UDL can give economical design–
(a) Square
(b) Circular
(c) I-Section
(d) Rectangular

Solutions

S1. Ans (c)
Sol. We know that
Kinetic energy correction factor (∝) = (K.E.based on actual velociy )/( K.E.based on Ideal velocity )
▭(∝ = (∫▒〖u^3 dA〗)/Av³).
As dimensions of numerator and denominator are same so, we can say that kinetic energy
correction factor (∝) is dimensionless or its dimension is M^0 L^0 T^0.

S2. Ans (a)
Sol. The Froude Number is a dimensionless parameter used in connection with open channel flow. For Fr < 1, flow is sub-critical; for Fr = 1, flow is critical and for Fr > 1, flow is supercritical

S3. Ans. (a)
Sol. Choke area (A)
A=m/(ρtɳ √2gH)
S4. Ans. (d)
Sol. Casting defects are blow holes, open blow, pin hole porosity, cuts and washes, metal penetration, fusion, runout, misrun and cold shut, slag inclusion hot tear and hot spot.

S5. Ans. (d)
Sol. moment of inertia of follow circular section
I=π/64 ( d_O^4-di_O^4 )
=π/64 (13^4-12^4 )
=384.1 cm^4
S6. Ans. (c)
Sol. I-section of a cantilever beam which is loaded with UDL will give must economical design as for strongest cross section, moment of resistance (M_R) should be maximum, which depend upon section modules (2). For same cross-sectional area, section modules of I-section is maximum, hence it will be most economical design.