Download July 2010

DME
TUTOR MARKED ASSIGNMENT
BET-022
STRENGTH OF MATERIALS
Maximum Marks : 100
Weightage : 30%
Course Code : BET-022
Last Date of Submission : November 15, 2010
Note : All questions are compulsory and carry equal marks.
Q.1 (a)
Define the following terms :
(i)
Factor of Safety
(ii)
Shear Stress and Shear Strain
(iii)
Modulus of Elasticity
(iv)
Resilience
(v)
Strain Energy
(b)
A tensile test is carried out on a bar of mild steel of diameter 2.25 cm. The bar yields
under load of 8 x 104 N; it attains a maximum load of 15 x 10 4 N breaks finally at a load
of 7 x 10 4 N. Estimate (i) tensile stress at yield point (ii) ultimate Stress (iii) average
stress at breaking point if the diameter of the neck is 1.2 cm.
Q.2 (a)
A Steel tube 3.2 cm internal diameter, 0.25 cm thick and 4 m long is covered and lined
throughout with copper tubes of 0.508 cm thick. The three tubes are firmly united at
their ends. This compound tube is subjected to tension and stress produced in the steel
tube is 60 MPa. Determine (a) the elongation of the tube, (b) stress in the copper tube,
(c) load carries by the combined tubes. Take Es = 2.1  1011 Pa and Ec =1.1  1011 Pa.
(b)
The efficiencies of longitudinal and circumferential joints in a cylindrical drum are 75%
and 40% respectively. The drum is 2250 mm long with wall thickness 12 mm. Find the
safe air pressure if the allowable stress in the shell material is 120 MPa.
Q.3 (a)
Discuss the various types of beam with suitable examples.
(b)
A beam 8.0 m long made of wood with a square cross-section (400 mm) is floating in
sea water. Two equal just sufficient weights are placed on the beam at 2.0 m away
from each end to immerse in the sea. Find the magnitude of the weights. Also draw
S.F.D and B.M.D for the beam. Take unit weight of timber and sea water 6400 N/m and
10200 N/m respectively.
Q.4 (a)
A simply supported beam having circular cross-section of diameter 0.01778 m is
loaded by the two concentrated load of 88.96 KN each applied 0.3048 from the ends of
the beam. Determine the maximum flexural stress in the beam.
(b)
Write some important points showing some characteristics of shear force and bending
moment diagrams.
Q.5 (a)
(b)
Q.6 (a)
(b)
Q.7 (a)
A beam of hollow square cross-section (5 cm x and 5 cm) with 0.6 cm uniform
thickness is subjected to shearing force 50 KN in the direction of one of the diagonal of
the cross section. Determine maximum shearing stress developed and draw shearing
stress distribution across the section.
Discuss the assumptions made in case of pure symmetrical bending.
Derive differential equation of deflection curve in a beam.
Draw the shear stress distribution diagram for a channel section (12 cm x 6 cm x
1.5 cm) of a beam subjected to shear force 50 KN at a Section. Also find the ratio
between the maximum and minimum shear stresses.
Derive the following expression, considering the theory of torsion.
T
 G
 
.
J

L
(b)
A solid circular shaft transmits 75 KW power at 200 r.p.m. Find the suitable diameter of
the shaft if the twist in the shaft not to exceed 10o in 2 meters length and shear stress is
limited to 50 MPa. Take G = 100 MPa.
Q.8 (a)
A flat steel bar, 25 mm wide by 6mm thick and 1 m long is bent by couples applied at
the ends so, that the mid point deflection is 20 mm. compute the stress in the bar and
magnitude of the couples. E = 200 GPA.
(b)
Determine Euler’s Crippling load for I-section just 40 cm x 20 cm x 1 cm and 5 m long
which is used as a column with both ends fixed. E = 2.0 X 105 MPa.
Q.9 (a)
(b)
Q.10 (a)
(b)
Discuss the Buckling Load and Slenderness Ratio.
An Allowable axial load for a column of a length l with both ends fixed is 30 KN. Three
different columns made of same material, same length and section having the following
end conditions : (i) Both the ends are hinged, (ii) one end is fixed other end is free and
(iii) one end is fixed, other end is hinged. What are the allowable loads for the three
columns with conditions given above?
Discuss the Euler Theory of column.
A Thin cylindrical Shell of diameter 500 mm and wall thickness t is subjected to an
internal pressure of 2 N/mm2. Determine the thickness of the cylinder according to the
maximum principal stress taking factor of safety as 3, if the yield strength of the
material.
DME
TUTOR MARKED ASSIGNMENT
BCE-025
ELEMENTARY CIVIL ENGINEERING
Maximum Marks : 100
Weightage : 30%
Course Code : BCE-025
Last Date of Submission : November 15, 2010
Note : All questions are compulsory and carry equal marks.
Q.1 (a)
(b)
Q.2 (a)
(b)
Q.3 (a)
(b)
Q.4 (a)
(b)
Q.5 (a)
(b)
Q.6 (a)
(b)
Q.7 (a)
Explain in detail the terms PERT and CPM used in construction planning.
Write a note on curing of concrete.
Discuss the common building stones and their uses.
Discuss and draw the double Flemish and English bond for double brick.
Explain in brief the construction of Cement Concrete road.
Discuss the commonly used paints in building constructions.
Discuss the types of hot rolled bars.
Discuss the different types of valves with sketch, used in water works practice.
Give a brief account of the sealants and joints fillers used in building construction.
Explain in brief plate load test with the help of a neat sketch.
What are the various features to be considered while locating window.
Enlist the different types of stairs with labeled sketches.
What are the types of doors? Draw labeled sketch.
(b)
Write significance of wind-rose diagram with reference to airport engineering.
Q.8 (a)
What is revetted joint? Explain the types of the revetted joint with neat sketch.
(b)
Q.9 (a)
(b)
Q.10 (a)
(b)
What is bulking of sand? Explain with sketch.
Write a difference between determinate and indeterminate structures.
Discuss the stages of survey in a highway alignment.
What is meant by foundation? Explain the functions of foundation.
Explain orthographic projection with suitable example.
DME
TUTOR MARKED ASSIGNMENT
BEE-031
ELECTRICAL TECHNOLOGY
Maximum Marks : 100
Weightage : 30%
Course Code : BEe-031
Last Date of Submission : November 30, 2010
Note : All questions are compulsory and carry equal marks.
.
Q.1 (a)
Explain Kirchhoff’s voltage AND currents Law. When writing the Kirchhoff’s voltage law
equation for a loop, how do we handle the situation when an ideal current source is
present around the loop.
(b)
Find the current flowing through the RL = 1 k Ω resistor for the circuit shown in Figure 1.
What is the power delivered or absorbed by the independent current source?
Figure 1
Q.2 (a)
For the circuit shown in Figure 2, find the current through R2 = RL = 1 k Ω resisters
(Ia – b).Branch using Norton’s theorem & hence calculate the voltage across the current
source.
Figure 2
(b)
Q.3 (a)
(b)
Give the statements of the following theorems.
(i)
Superposition Theorem
(ii)
Thevenin’s Theorem.
Explain and prove Maximum power transfer theorem.
A 200 V, 50 Hz supply is connected to a resistance (R) of 20 Ω in series with an iron
cored choke coil (r in series with L). The readings of the voltmeters across the
resistance and across the coil are 120 V and 150 V respectively. Find the loss in the
coil. Also find the total power factor. Draw the phasor diagram.
Q.4 (a)
Find the input voltage at 50 Hz to be applied to the circuit shown in Figure 3 such that
the current in the capacitor is 8 A?
Figure 3
(b)
Q.5 (a)
(b)
Explain the condition of resonance in RLC series circuit. Enlist the effect of resonance
in the circuit.
Draw the complete phasor diagrams of a single phase transformer when :
(i)
the load in the secondary is purely resistive, and
(ii)
secondary load power factor is leading.
In Figure 4, the ideal transformer has turns ratio 2 : 1. Draw the equivalent circuits
referred to primary and referred to secondary. Calculate primary and secondary
currents and the input power factor and the load power factor
Figure 4
Q.6 (a)
An ideal autotransformer steps down a 400 V, single phase voltage to 200 V, single
phase voltage. Across the secondary an impedance of (6 + j8) Ω is connected.
Calculate the currents in all parts of the circuit.
(b)
A 4-pole, lap wound, DC machine has total number of 800 armature conductors and
produces 0.03 Wb flux per pole when field is excited. If the machine is driven by a
prime mover at 1000 rpm, calculate the generated EMF across the armature. If the
generator is loaded to deliver an armature current of 50 A, Calculate the prime mover
and electromagnetic torques developed at this load current. Neglect frictional torque.
Q.7 (a)
A d.c motor takes an armature current of 50 A at 220 V. The resistance of the armature
is 0.2 Ω. The motor has 6 poles and the armature is lap wound with 430 conductors.
The flux per pole is 0.03Wb. Calculate the speed at which the motor is running and the
electromagnetic torque developed.
(b)
Derive the expression for the generated voltage in a d.c generator. Write down the
expression for electromagnetic torque in a d.c motor.
Q.8 (a)
(b)
Draw and explain the Torque- Slip characteristic of 3-phase Induction Motor.
Give the various methods of starting of single phase motor. Explain any one of them.
Q.9 (a)
Explain the working principle of synchronous motor with neat sketch. Give its
applications.
(b)
The armature of 8 pole, 3-phase,50 Hz alternator has 17 slots and has 10 conductors
per slot. There are 0.04 Wb entering the armature from 1 pole.Assume the flux to be
distributed sinusoidal along the air gap. Calculate the induced EMF per Phase.
Q.10 (a)
(b)
Show the phasor diagram of alternator for Leading power factor.
Give the advantage of rotating field generator.
DME
TUTOR MARKED ASSIGNMENT
BET-034
MACHINE DRAWING
Maximum Marks : 100
Weightage : 30%
Course Code: BET- 034
Last Date of Submission: November 30, 2010
Note : All questions are compulsory and carry equal marks.
Q.1 (a)
What are the two systems of placing dimensions on a drawing? Explain them with
suitable sketches.
(b)
Explain the difference between Isometric projection and oblique projection with suitable
diagrams.
Q.2 (a)
Draw the front view, side view and top view of the hexagonal prism with 50 mm side
and 200 mm height. Assume one face of the prism is parallel to vertical plane.
(b)
Describe about the sectional view with suitable examples.
Q.3 (a)
Two 8 mm thick plates are bolted by passing the 10 mm major diameter bolt through
11 mm diameter hole. The nut is tightened on top. Draw the dimensioned front view.
(b)
Draw a bolted joint in section (front view) between circumference of a cylinder and
cover. Cylinder diameter = 400 mm. Number of bolts 12. Pitch circle diameter of bolts
= 480 mm, M 20 bolts with d = 20mm, p = 2.5 mm and d1 = 17.3 mm is tube used.
Q.4 Draw two suitable views of Eye Foundation bolt (D = 25 mm) of Figure 1.
Figure 1
Q.5 (a)
(b)
Q.6 (a)
Two 20 mm thick plates are joined in double riveted but joint. Find the rivet hole
diameter, margin, pitch and back pitch for chain riveting, draw the front sectional view
and plan.
What is welded joint? Explain the types of the welded joint with neat sketch.
Explain with the help of sketches, the use of (i) a woodruff key and (ii) a cone key.
(b)
On a 35 mm diameter shaft carries a pulleys of 900 mm diameter whose hub tapers
from 75 mm at the arm to 70 mm at the edge end is 80 mm long. Four arms, elliptic in
section from a1 = 26 mm to a = 20 mm and b1 = 12 mm to b = 30 mm. Show the
assembly of pulleys with gib headed key and with part of shaft whose diameter
increases to 45 mm from 35 mm suddenly with radius of 5 mm at the corner. The width
of the pulleys is 1000 mm with 9 crown of 3 m. Rim thickness at edges, 8 mm.
Q.7 (a)
Make a neat dimensioned sketch of a flanged joint for two 100 mm diameter C.I. Pipes.
(b)
What is bearing? Explain the types of the bearing with neat sketch?
Q.8 The details of screw jack are given in Figure 2. Assemble the parts and draw elevation plan
side view of the assembly.
Figure 2
DME
TUTOR MARKED ASSIGNMENT
BME-052
BASICS OF THERMAL ENGINEERING
Maximum Marks : 100
Weightage : 30%
Course Code : BME-052
Last Date of Submission : November 15, 2010
Note : All questions are compulsory and carry equal marks.
Q.1 (a)
What is thermodynamics? Explain the first law of thermodynamics with suitable
example.
(b)
State explains Zeroth law of thermodynamics. Distinguish between intensive properties
and extensive properties by giving examples.
(5 + 5 = 10)
Q.2 A system receives 200 kJ of heat at constant volume. Then it is cooled at constant pressure,
when 50 kJ of work has done on the system while it rejects 70 kJ of heat. Supposing the
system is restored in the initial state by an adiabatic process, how much work will be done by
the system?
(10)
Q.3 (a)
Steam initially at 1.5 MPa, 300oC expands reversibly and adiabatically in a steam
turbine to 40oC. Determine the ideal work output of the turbine per kg of steam. Show
the process on T-s and h-s diagram.
(b)
A pressure cooker contains 1.5 kg of dry saturated steam at 5 bar. Find the quantity of
heat which should be removed to reduce the quality of steam to 60% dry.
(5 + 5 = 10)
Q.4 What is a boiler? How the boilers are classified? Describe the working of Cochran boiler with
neat diagram. Also explain some of its applications.
(10)
Q.5 (a)
What is rankine cycle? Describe the effects of pressure and temperature on rankine
cycle.
(b)
Steam enters the turbine of reheat rankine cycle at 5 MPa, 400 oC. After expansion in
the turbine to 4 bar it is taken to a reheater and heated at 400oC and sent to the low
pressure turbine. If the condenser pressure is 10 KPa, determine the cycle efficiency.
(3 + 7 = 10)
Q.6 (a)
What is a condenser? What are the types of condensers? Using a neat sketch, explain
the construction and working of surface condenser.
(b)
Briefly describe the construction and working of any one type of induced draft type
cooling tower.
(5 + 5 = 10)
Q.7 (a)
What are the functions of air pre-heater, economizer and re-heater in a power plant?
Explain in detail the feed water-steam circuit.
(b)
Define conduction, convection and radiation? What is a black body? Also explain the
Stefan-Boltzmann law of thermal radiation.
(5 + 5 = 10)
Q.8 (a)
What is solar energy? Give some applications of solar energy. Describe the
construction of solar flat plate collector.
(b)
Draw neat sketch of a tidal power plant and explain the construction and working. Also
list the advantages and limitations of a tidal power plant.
(5 + 5 = 10)
Q.9 (a)
(b)
When a stationary mass of gas was compressed without friction at constant pressure
its initial state of 0.4 m3 and 0.105 MPa was found to change to final state of 0.20 m3
and 0.105 MPa. There was a transfer of 42.5 kJ of heat from the gas during the
process. Find, how much did the internal energy of the gas change?
A cylinder containing the air comprises the system. Cycle is completes as follows :
(i)
82000 Nm of work is done by the piston on the air during compression stroke
and 45 kJ of heat are rejected to the surroundings.
(ii)
during expansion stroke 100000 Nm of work is done by the air on the piston.
Calculate the quality of heat added to the system.
(4 + 6 = 10)
Q.10 (a)
If a barometer stands at 760 mm and condenser vacuum is at 710 mm and
temperature is 30oC, calculate the mass of air per kg of uncondensed steam.
(b)
Steam enters a condenser at 36oC and with barometer reading 760 mm. If the vacuum
of 695 mm is produced, find the vacuum efficiency. Use steam tables.