Code No: V0221
II B.Tech II Semester (R07) Regular/supply Examinations, Apr- 2010
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Common to EEE, EIE, BME, E.CON.E)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Explain the importance of Managerial Economics in decision making.
2. What is demand forecasting? Explain different methods of demand forecasting.
3. Explain different cost concepts which are essential for business decisions.
4. Define Monopoly. Explain price and output determination under monopoly.
5. What is partnership? What are its features, advantages and disadvantages?
6. A company estimates its fixed costs for the year at Rs. 8, 00,000 and its profit
target at Rs. 2, 00,000. Each unit of product is sold at Rs. 10 and variable cost per
unit is Rs. 8. What sales level must the company achieve in order to realize its
profit goal?
7. What is accounting? Explain the double-entry system of accounting rules with
their formulae.
8. The following is the balance sheet of ABC Ltd. as on 31-3-2009.
Liabilities Amount
(in Rs.)
Assets Amount
(in Rs.)
Preference dividend 5,00,000 Short term investment 1,00,000
10% long term loan 3,25,000 Stock as on 1-1-2006 1,44,000
14% debentures 1,50,000 Sundry Debtors 1,75,000
Sundry creditors 75,000 cash 10,000
Bills payable 30,000 Prepaid expenses 15,000
Bank overdraft 25,000 Cost of goods sold 6,00,000
Share capital (fund) 3,00,000 Stock as on 31-1-2006 2,56,000
Total 14,05,000 14,05,000
Calculate the following ratios:
a) Current ratio
b) Quick ratio
c) Debt-equity ratio
d) Stock turnover ratio
1 of 1
SET - 1
Code No: V0221
II B.Tech II Semester (R07) Regular/supply Examinations, Apr- 2010
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Common to EEE, EIE, BME, E.CON.E)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Explain how Managerial Economics is linked with other academic disciplines.
2. Define Law of Demand. What are its exceptions? Explain.
3. Illustrate the price determination in case of monopoly.
4. Explain the cost concepts and their role in managerial decisions.
5. Evaluate sole proprietorship form of business organization.
6. If sales are 10,000 units and selling price is Rs. 20 per unit, variable cost Rs. 10 per unit
and fixed cost is Rs. 80,000. Find out BEP in units and sales revenue. What is profit
earned? What should be the sales for earning a profit of Rs. 60,000/-.
7. Explain the following ratios with their formulae.
a) Current ratio
b) Quick ratio
c) Debt-equity ratio
d) EPS
e) Net profit ratio
8. From the following trail balance to prepare Trading account, Profit and loss account and
Balance sheet as on 31-3-2007.
Sales 4,00,000 Sundry debtors 1,20,000
Capital 50,000 Carriage inwards 2,500
Land 50,000 Bad debts 10,000
Opening stock 20,000 Carriage outwards 75,000
Wages 5,000 Salaries 60,000
Purchase Returns 10,000 Rent (credit) 20,000
Interest 5,000 Bills payable 30,000
Sundry Creditors 60,000 Buildings 70,000
Furniture 60,000 Purchases 1,00,000
Rent 10,000 Bills receivable 50,000
Adjustments:
1. Closing stock Rs. 60,000
2. Outstanding wages--- Rs. 1000
3. Doubtful debts on sundry debtors @ 5%
4. Depreciation on furniture @ 10% and on buildings @ 10%
1 of 1
SET - 2
Code No: V0221
II B.Tech II Semester (R07) Regular/supply Examinations, Apr- 2010
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Common to EEE, EIE, BME, E.CON.E)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Discuss the nature and scope of Managerial Economics.
2. What is Elasticity of Demand? How do you measure it?
3. Define returns to scale. What is the significance of increasing, decreasing and constant returns to
scale?
4. What is the perfect competition? How are price and out determined under perfect
Competition?
5. Define sole trader. What are its features and merits and demerits?
6. XYZ Company has supplied you the following information.
No. of units sold 20,000 units
Fixed cost Rs. 2, 40, 000
Variable cost per unit Rs. 15
Selling price per unit. Rs. 30
Find out:
a) BEP in units
b) Margin of safety
c) Sales to get a profit of Rs. 2,00,000
d) Verify the results in all the above cases
7. What is ratio? Explain the analysis and interpretation of liquidity ratios and
profitability ratios
8. From the following trail balance, prepare the Trading account, profit& Loss account and Balance
sheet as on 31-3-2008.
Opening stock 30,000 Wages 1,000
Purchase 45,000 Sales 70,000
Sales Returns 3,000 Purchase returns 2,000
Carriage inwards 1,000 Power & fuel 500
Salaries 1,000 Interest 2,000
Rent 500 Insurance 500
Bad debts 500 Commission (Credit) 10,000
Capital 80,000 Discount (credit) 15,000
Creditors 30,000 Bank overdraft 10,000
Cash at bank 15,000 Machinery 40,000
Land & buildings 50,000 Sundry debtors 50,000
Adjustments:
a) Closing stock Rs. 40,000
b) Prepaid carriage inwards Rs. 500
c) Deprecation on land & buildings @ 10%
d) Deprecation on Machinery @ 10%
e) Bad debts on sundry debtors @ 5%
Code No: V0221
II B.Tech II Semester (R07) Regular/supply Examinations, Apr- 2010
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Common to EEE, EIE, BME, E.CON.E)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Define Managerial Economics. Explain the nature and scope of Managerial Economics.
2. Define the Law of Demand. What are its Exceptions? Explain.
3. What is perfect competition? Explain the equilibrium of firm and industry in both the shortrun
and long-run under perfect competition.
4. Define production function? What are the types of production function? Explain them in
brief.
5. Discuss the role of sole proprietorship in forms of organization.
6. What is accounting? Explain the accounting concepts and conventions.
7. A firm manufactures two products viz. P and Q. The firm wants to drop the product Q as it is
yielding less contribution per unit and add the product R. By adding the product R, the new
fixed cost is likely to be Rs. 2,50,000/- and the sales volume will increase to Rs.18,00,000/-
Consider the following information and suggest whether the firm should change the
product or not.
Existing Product-mix
Product Selling price/ per unit
(Rs.)
Variable cost/ per unit
(Rs.)
% of sales
P 80 32 60
Q 100 40 40
The total fixed cost during the year is Rs. 200,000/- and sales are Rs. 16,00,000/-
Proposed Product-mix
Product Selling price/ per unit
(Rs.)
Variable cost/ per unit
(Rs.)
% of sales
P 100 40 30
R 120 48 70
8. The following is the balance sheet of ABC Ltd. as on 31-3-2009.
Liabilities Amount
(in Rs.)
Assets Amount
(in Rs.)
Sales 3,00,000 Gross profit 1,50,000
Sale returns 50,000 Cost of goods sold 60, 000
No. of equity shares
15,000 @ Rs. 10/-
1,50,000 Office expenses 20,000
Preference dividend 50,000 Selling expenses 15,000
Sundry creditors 10,000 Profit after tax 3,00,000
Bills payable 30,000 Stock 15,000
Total 5,60,000 5,60,000
Calculate the following ratios:
a) Gross profit ratio
b) Net profit ratio
c) EPS
d) Price earning ratio
e) Operating ratio
Code No: V0222/R07 Set No. 1
II B.Tech II Semester Regular Examinations, April 2010
LINEAR AND DIGITAL IC APPLICATIONS
( Common to Electrical & Electronic Engineering and Instrumentation &
Control Engineering)
Time: 3 hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) What is an Op-amp? Why it is called so?
(b) Explain the parameters that should be considered for ac and dc applications
of an Op-amp?
(c) Draw and explain the two open loop Op-amp configurations with neat circuit
diagram. [4+5+7]
2. (a) Explain the operation of Zero crossing detector.
(b) Briefly mention the disadvantages of using Zero crossing detector and how it
is overcome in Schmitt Trigger?
(c) Draw a circuit using Op-amp which can work as adder (inverted and non-
inverted) and explain how it works. [4+4+8]
3. (a) The cutoff frequency of a certain first order low pass filter is 2 KHz. Convert
this low pass filter to have a cutoff frequency of 3 KHz by using the frequency
scaling technique.
(b) How do we get a Notch filter from a band pass filter.
(c) What are the advantages of active filters over passive filters. [8+4+4]
4. (a) Explain the significance of each of comparator and also operation of 555 timer.
(b) Explain the application of 555 timer as Linear ramp generator. [8+8]
5. (a) With an example explain the functional diagram of successive approximation
ADC.
(b) Draw the schematic circuit diagram of a Servo A/D converter and explain the
operations of this system.
(c) Compare Servo A/D with other types of A/D converters. [7+6+3]
6. (a) Design a TTL three-state NAND gate and explain the operation with the help
of function table?
(b) What are the parameters that are necessary to define the electrical character-
istics of CMOS circuits? Mention the typical values of a CMOS NAND gate?
[8+8]
7. (a) Using two 74×138 decoders design a 4 to 16 decoder?
1 of 2
Code No: V0222/R07 Set No. 1
(b) Design a CMOS transistor circuit that has the functional behavior F(Z) =
(A + ¯B )(B + C). [8+8]
8. (a) Distinguish between synchronous and asynchronous sequential circuits.
(b) Write short notes on static RAM. [8+8]
? ? ? ? ?
Code No: V0222/R07 Set No. 2
II B.Tech II Semester Regular Examinations, April 2010
LINEAR AND DIGITAL IC APPLICATIONS
( Common to Electrical & Electronic Engineering and Instrumentation &
Control Engineering)
Time: 3 hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) An op-amp has a slew rate of 2V/μs. What is the maximum frequency of an
output sinusoid of peak value 5V at which the distortion sets in due to the
slew rate limitation. Derive the formulae used.
(b) If the sinusoid of 10V peak is specified, what is the full power band width?
(c) List out the non ideal Dc characteristics of an Op-amp? [8+4+4]
2. (a) Draw an integrator circuit and explain its operation. Discuss the frequency
response for a practical integrator.
(b) Explain how an Op-amp can be used as summing amplifier? Draw the diagram
of a four input summer.
(c) Explain the operation of a scale changer with circuit diagram. [6+6+4]
3. (a) Explain the term “Frequency Scaling” with suitable example.
(b) Design a I order wide band-pass filter with fL=200 Hz. fH=1 KHz and a pass-
band gain=4. Draw the frequency response and calculate ?Q? factor for the
filter. (Assume necessary data) [6+10]
4. Explain the functional block diagram of PLL emphasizing the importance of capture
range and Lock range. [16]
5. (a) Draw the circuit of a Ladder type DAC for 4 bits and derive expression for
output voltage.
(b) Sketch the Analog output voltage for the given digital code.
(c) Compare R-2R and Weight Resistor types of ADC. [8+4+4]
6. (a) Draw a circuit of a CMOS NAND gate and explain?
(b) Compare TTL and CMOS IC characteristics.
(c) List out different categories of characteristics in a TTL data sheet? Discuss
electrical and switching characteristics of 74LS00. [4+6+6]
7. (a) Design 2 bit comparator using gates?
(b) Design an 8 bit adder using two 74283IC. [8+8]
8. (a) Write short notes on Johnson counter.
(b) Write short notes on DRAM. [8+8]
? ? ? ? ?
Code No: V0222/R07 Set No. 3
II B.Tech II Semester Regular Examinations, April 2010
LINEAR AND DIGITAL IC APPLICATIONS
( Common to Electrical & Electronic Engineering and Instrumentation &
Control Engineering)
Time: 3 hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) For an inverting Op-amp having R1 = 470, feedback resistor RF = 4.7K
and Calculate Closed loop gain, Bandwidth with feed back, Input resistance,
Output Resistance.
(b) Derive the formulae used in solving part (a). [8+8]
2. (a) Briefly describe three uses of an analog multiplier.
(b) What do you mean by sampling? Explain the basic circuit for sample and
hold circuit. [8+8]
3. (a) Design a triangular wave generator using a comparator block and an integrator
block to oscillate at 4KHz and Vo(P-P)=7 V use an Op-amp with ±15 volt
power supplies. Make necessary assumptions.
(b) What is the purpose of back to back set of two zener diodes?
(c) What is the main advantage of comparator based triangular wave generator
over free running astable multivibrator based circuit? [8+4+4]
4. (a) Draw the schematic circuit diagram of the following and explain their working.
i. Analog phase detector.
ii. VCO.
Derive necessary expressions.
(b) What is their role is in PLL? Explain. [6+6+4]
5. (a) Draw the circuit of Weighted Resistor DAC and derive expression for output
analog voltage Vo.
(b) Give the schematic circuit of an A/D converter widely used in digital volt-
meters and explain its operation. Derive expression for output voltage. [8+8]
6. (a) With neat circuit explain the operation of TTL inverter.
(b) Briefly explain the different types of TTL gates.
(c) Explain the effect of floating inputs on CMOS gate? [5+7+4]
7. (a) Give the logic diagram of 74×138 and explain its truth table?
(b) Write short notes on BCD to Excess 3 code converter. [8+8]
8. (a) Design 4 bit left shift register with serial in and parallel out facility. Show the
output waveform of each flip flop output.
(b) Explain the functional behavior of Static RAM cell? Show the internal struc-
ture of 8×4 static RAM? [8+8]
2 of 2
Code No: V0222/R07 Set No. 4
II B.Tech II Semester Regular Examinations, April 2010
LINEAR AND DIGITAL IC APPLICATIONS
( Common to Electrical & Electronic Engineering and Instrumentation &
Control Engineering)
Time: 3 hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
? ? ? ? ?
1. (a) Draw and explain the internal block schematic of an Op-amp.
(b) Explain how the voltage follower is derived from a special case of non-inverting
amplifier. [8+8]
2. (a) Explain the non-linear application of Op-amp as logarithmic and anti loga-
rithmic amplifier.
(b) Design a Integrator to integrate an I/P signal that varies in frequency from 1
KHz to 10 KHz and plot the O/P wave forms if the I/P is a sine wave of 1V
peak at 1 KHz. [10+6]
3. (a) State and briefly explain Barkhausen criterion for oscillation.
(b) Draw the schematic diagram of a fourth order low pass butter worth filter and
design it with upper cut off frequency of 1KHz. [6+10]
4. Discuss the significance of phase detector, Low pass filter, amplifier and a VCO in
PLL. [4 × 4=16]
5. (a) Compare weighted resistor D/A converter and R-2R D/A converter.
(b) Why successive approximation A/D converter is preferable than parallel com-
parator A/D converter. Explain.
(c) Draw the schematic block diagram of Dual-slope A/D converter and explain
its operation. Derive expression for its output voltage Vo. [2+4+10]
6. (a) With relevant circuit and characteristics explain fan in and fan out of TTL
ICS.
(b) Explain the functions of a Tri-state TTL gate.
(c) Explain the TTL ICs application circuits. [6+4+6]
7. (a) Design a n bit priority encoder.
(b) Design a 3 bit BCD adder circuit and explain its working. [8+8]
8. (a) Explain with an example why asynchronous inputs are required in flip flops.
(b) Explain the operation of edge triggered T flip- flop. [8+8]
Code No: T0222
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ELECTRICAL MACHINES - II
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Derive the EMF equation of a single phase transformer? Comment on different values of
transformation Ratio. (8M)
b) The approximate e.m.f/turn of 11000V/415V, 50Hz, 1- _ transformer core type
transformer is 15V, maximum flux density is 1.5tesla. Find suitable number of primary and
secondary turns and net cross sectional area of the core. (8M)
2. a) Explain various losses existing in transformer and hence derive the condition for
maximum efficiency of a transformer. (8M)
b) The maximum efficiency of 50 KVA transformer is 97.4% and occurs at 90% of the full
load. Calculate the efficiency of transformer at
( i) Full load, 0.8 power factor lagging
(ii) Half full load, 0.9 power factor lagging (8M)
3. a) From fundamentals, develop the neat diagram of approximate equivalent circuit of
transformer (8M)
b) A 10 KVA, 2000/400 V, 1-_ transformer has resistance and leakage reactance as follows
R1 = 50_; X1 =12.5_; R2 =0.2_; X2 =0.5_. Determine the secondary terminal voltage when
it is supplying rated current at 0.8 lagging factor. Neglect no-load current. (8M)
4. a) With neat phasor diagram, explain the voltage regulation of three-phase transformer.
(8M)
b) An ideal three phase step down transformer connected in delta/star delivers power to a
balanced 3-phase load of 120 kVA at 0.8 pf. The input line voltage is 11 kV and the turn’s
ratio of transformer (phase to phase) is 10. Determine the line voltage, line currents, phase
voltages, phase currents on both primary & secondary sides. (8M)
5. a) Explain the differences between squirrel cage and Slip ring Induction Motor. (8M)
b) The power input to a 3-_ Induction Motor is 100KW. The stator losses are equal to 2KW.
Find the mechanical power output and rotor copper losses; if the motor runs with a slip of
4%. Mechanical losses are equal to 2.5KW. (8M)
6. a) Obtain the ratio of Maximum torque to Full load torque & Maximum torque to staring
torque in 3-_ Induction Motor. (8M)
b) A 4-pole, 50 Hz, 3-f Induction Motor has rotor impedance of (0.04 + j 0.16) _. Calculate
the value of external rotor resistance to be inserted in rotor circuit to obtain 70 % of
maximum torque at starting. (8M)
7. a) With neat diagram explain the construction & operation of auto transformer starting
method of 3-_ Induction Motor. (8M)
b) The short circuit current of a squirrel cage Induction Motor on normal voltage is 3.5 times
the full load current & the full load slip is 4 %. Determine the percentage tapping required to
an auto transformer starter to start the motor against 1/3rd full load torque. Neglect
magnetizing current. (8M)
8. a) Compare the speed control of 3-f Induction Motor by rotor resistance control & variable
frequency control. (8M)
b) If the star connected rotor winding of a 3-_ Induction Motor has a resistance of 0.01
_/phase and stand-still leakage reactance of 0.08 _/phase. Calculate the value of the
additional resistance/phase to be introduced in the rotor to give the maximum starting
torque. Also, estimate the percentage slip when the starting resistance has been reduced to
0.02_/phase if the motor is still exerting the maximum torque. (8M)
Code No: T0222
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ELECTRICAL MACHINES - II
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Draw and Explain Phasor diagram of single phase transformer operating on no load.
(8M)
b) A 1-_, 440V/110V, 50Hz transformer takes a no load current of 5A at 0.2 power factor
lagging. If the secondary supplies a current of 120 A at a power factor of 0.8 lagging to a
load, determine the primary current and the primary power factor. Also, draw the phasor
diagram. (8M)
2. a) Derive the condition for maximum efficiency of a transformer. (8M)
b) A single phase 150 kVA transformer has efficiency of 96 % at full load, 0.8 pf and at half
load, 0.8 pf lagging. Find maximum efficiency of transformer and corresponding load.
(8M)
3. a) What is auto transformer? How auto transformer is different from ordinary two winding
transformer? What are the advantages & disadvantages of auto transformer? Explain the
working principle of auto transformer (8M)
b) Obtain the derivation for the copper saving in auto transformer compared to two winding
transformer for identical rating. (8M)
4. a) Discuss the constructional details of the three phase transformers with necessary
diagrams. Mention their advantages and disadvantages. (8M)
b) Explain the principle of 3-_ to 2-_ conversion using Scott connection. Draw the phasor
diagram of Scott connected transformer showing phase relationships of currents in case the
secondary of teaser transformer supplying Unity pf load and secondary of main transformer
is supplying load at 0.8 p.f lagging. (8M)
5. a) Explain why the rotor of polyphase induction motor can never attain synchronous speed.
(8M)
b) Discuss the points of similarities between a transformer and an induction machine. Hence,
explain why an induction machine is called a generalized transformer. (8M)
6. a) Explain the torque development process in an induction motor and its dependence on
rotor slip. (8M)
b) The power Input to Rotor of a 440V, 50Hz, 6-pole, 3-_ Induction Motor is 100KW. The
Rotor electromotive force is observed to make 120 cycles per minute. Calculate i) Slip, ii)
Rotor speed, iii) Mechanical power developed and iv) Speed of stator field with respect to
rotor (8M)
7. a) What are the various types of starters used for squirrel cage rotors? Discuss them. (8M)
b) A Squirrel Cage Induction Motor has a stating current of six times the Full-load current at
a slip of 0.04. Calculate the line current and Starting torque in p .u of full-load values for the
following methods of starting:
(i)Direct switching
(ii) Star-delta starting. (8M)
8. a) Explain the principle of operation of induction generator (8M)
b) Explain briefly the different methods of speed control from stator side of 3 phase
induction motor. (8M)
Code No: T0222
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ELECTRICAL MACHINES - II
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Draw and Explain Phasor diagram of single phase transformer operating on lagging load.
(8M)
b) A transformer on load takes 1.5 Amps at a power factor of 0.2 lagging when connected
across 50Hz, 230V supply. The ratio between primary and secondary number of turns is 3.
Calculate the value of primary current when secondary is supplying a current of 40 amps at
a power factor of 0.8 lagging. Neglect the voltage drop in the windings. Draw the relevant
phasor diagram. (8M)
2. a) Define efficiency and regulation of a transformer. Show how the power factor affects both
of them (8M)
b)A single phase 150KVA transformer has efficiency of 96% at full load, 0.8 pf and at half
load, 0.8 pf lagging. Find the maximum efficiency of transformer and corresponding load.
(8M)
3. a) What are the conditions required for the parallel operation of two transformers. (8M)
b)Two transformers A and B are connected in parallel to a load of (2+j1.5) _. The
Impedance in secondary are ZA = (0.15+j0.15) _, ZB= (0.1+j0.1) _. Their no load terminal
voltage are EA=(207+j0) V, EB= (205+j0) V. Find power output and Power factor of each
transformer. (8M)
4. a)Why is it preferable to operate a bank of transformers rather than three independent single
phase transformers? (8M)
b)The no-load current of a transformer is 5.0A at 0.3 power factor when supplied at 230V,
50Hz. The number of turns on the primary winding is 200. Calculate
i) The maximum value of the flux in the core
ii) The core loss and
iii) The magnetizing current. (8M)
5. a) Explain with neat diagrams the construction and working of a 3 phase induction motor.
(8M)
b)A balanced 3 phase induction motor has an efficiency of 0.85 when the output is 60HP. At
this load the stator and rotor copper losses are equal to the core losses. The mechanical
losses are ¼ of no load loss. Calculate the slip. (8M)
6. a) Show that in an induction motor the rotor input: power developed: rotor copper losses ::
1: (1-s) : s, where ‘s’ is the fractional slip. (8M)
b) A 3 phase star connected 220V (line to line), 50Hz, 4 pole induction motor has the
following constants in ohm/phase: r1 = 0.3, r2 =0.15, X1 =0.5, X2 =0.2 and magnetizing
reactance X0=14 ohm. The total friction, windage and core losses may be assumed to be
constant at 420W independent of load. For slip of 2%, calculate (i) speed (ii) Output torque
and (iii) Stator current of the motor. (8M)
7. A 3 f, D connected, 20 HP, 440 V, 6-pole, 50 Hz Induction Motor gave the following test
results:
No load Test: 440 V, 10 A, p.f = 0.2
Blocked rotor test: 200 V, 50 A, p.f = 0.4
All above are the line values. Plot the circle diagram and for full load find:
(a) The line current
(b) The power factor
(c) Slip
(d) Torque
(e) Efficiency
(f) Maximum Power factor
Given that rotor copper losses are equal to stator copper losses at stand still. (16M)
8. a) Explain the speed control of 3-f Induction Motor using 'rotor emf injection method'.
(8M)
b) A 2-pole, 3-f, 50 Hz, slip ring induction motor has its rotor resistance of 0.2W/ph and full
load speed of 2900 rpm. Calculate the external resistance per phase required to be added in
rotor circuit to decrease the speed to 2500 rpm. The torque remains the same as before.
(8M)
2 of 2
SET - 3
Code No: T0222
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ELECTRICAL MACHINES - II
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Explain the constructional details of a single phase transformer?
(8M)
b) When a 1-_ transformer is supplied at 400V, 50Hz the hysteresis loss is found to be
310W and eddy current loss is found to be 260W. Determine the hysteresis loss and eddy
current loss when the transformer is supplied at 800V, 100Hz.
(8M)
2. a) Write a short note on All-day efficiency of the transformer. (8M)
b) Find the All day efficiency of single phase transformer having maximum efficiency of
98 % at 15 KVA at UPF and loaded as follows.
12 hours — 2 KW at 0.5 power factor lagging
6 hours — 12 KW at 0.8 power factor lagging
6 hours — no load (8M)
3. a) Explain the procedure for conducting Sumpner’s test along with all precautions to be
taken while conducting the test with neat diagram.
(8M)
b) The corrected instrument readings obtained from short circuit test on 10 KVA, 450/125V,
50Hz transformer are 9.65V, 22.2A, 120W, with low voltage winding short circuited.
Compute voltage regulation for an 85% lagging load at 50% load.
(8M)
4. a) Discuss the constructional details of the three phase transformers with necessary
diagrams. Mention their advantages and disadvantages.
(8M)
b) A 3-f, 1200 kVA, 6.6/1.1 kV transformer has Delta/Star connection. The per phase
resistance is 2W and 0.03 W on primary & secondary respectively. Calculate the efficiency
on full load at 0.9 pf lagging, if iron losses are 20 kW. (8M)
5. a) Explain the classification of induction motors based on construction of rotor. Explain the
advantages & disadvantages of each.
(8M)
b) The frequency of stator EMF is 50 Hz for an 8-pole induction motor. If the rotor
frequency is 2.5 Hz, calculate the slip and the actual speed of rotor. (8M)
6. a) Explain the torque development process in an induction motor and its dependence on
rotor slip. (8M)
b) A3-_ Induction motor has a 4-pole Star connected stator winding and runs on 220V,
50Hz supply at 1425rpm. The rotor resistance is 0.1_ and reactance is 0.9_. The
transformation ratio is 0.57. Calculate
i) The total torque
ii) The maximum torque and
iii) The speed at maximum torque (8M)
7. Discuss the various types of starters used for starting the slip ring induction motors?
(16M)
8. a) Explain the speed control of Induction Motor by rotor resistance control method. How
this method of speed control is different from stator side speed control methods. (8M)
b) The rotor of 3-phase slip ring induction motor has an induced voltage of 100V and
impedance of (0.2+j1) ohm at stand still. The induction motor has full load slip of 0.04
driving constant torque load and running at 1440 rpm. Calculate the voltage to be injected if
the motor is to be driven at
(i) 800 rpm
(ii) 1000 rpm
Code No: V0122
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ENVIRONMENTAL STUDIES
(Common to CE, EEE, ME, CSE, EIE, BME, IT, E.Con.E, BOT)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Describe how you would methodically record the elements and resources in an
ecosystem and assess its functioning.
b) “Fuel powered ecosystems are man’s wealth generating and also pollution generating
systems” – Justify.
2. a) What are the various reasons for increase in population in India?
b) Suggest suitable measures for population control and discuss the merits of population
control.
3. a) What do you understand by the term ‘Biodiversity’? Discuss in detail.
b) What are the different services that are contributed in various ways by biodiversity?
4. Discuss the impact of science and technology on environment with suitable examples.
5. a) Discuss the phenomenon of global warming along with its effects and control
measures.
b) What are the impacts of thermal pollution on global warming?
6. a) Discuss the concept of sustainable development.
b) What are the major obstacles in the path of sustainable development in India?
7. Discuss the environmental impacts of irrigation and hydro-power projects.
8. a) Discuss the various methods for e-waste management?
b) Discuss the hazards of Biochemical wastes and explain the necessity to manage
these wastes?
1 of 1
SET - 1
Code No: V0122
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ENVIRONMENTAL STUDIES
(Common to CE, EEE, ME, CSE, EIE, BME, IT, E.Con.E, BOT)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Give an account of the structure and functions of an ecosystem.
b) Discuss the way in which ecosystems are destroyed by human activities.
2. a) Discuss population explosion in Indian context.
b) What should be the objectives of a sound population policy?
3. a) Why is it necessary to maintain biodiversity?
b) Discuss In-Situ and Ex-Situ conversation measures of biodiversity with suitable
examples.
4. Discuss the role of information technology and value education in environment and
human health.
5. Discuss the global effects of pollution and suggest suitable measures.
6. a) What do you understand by ‘Sustainable Life Styles’?
b) Explain suitable measures for sustainable development with suitable examples.
7. Discuss the environmental impacts of irrigation and hydro power projects.
8. a) Discuss the problems associated with resettlement and rehabilitation of people?
b) Discuss the Ozone depleting substances. Explain the measures to be taken to reduce
their Release?
1 of 1
SET - 2
Code No: V0122
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ENVIRONMENTAL STUDIES
(Common to CE, EEE, ME, CSE, EIE, BME, IT, E.Con.E, BOT)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. What is an environment? Enumerate and discuss the various segments of environment in
brief.
2. a) Explain about various forest resources.
b) What are the causes and effects of deforestation?
3. a) Explain about the structure and functions of an ecosystem.
b) Discuss the role of producers, consumers and decomposers in an ecosystem.
4. a)Discuss the main causes of Poaching. How do you protect Wildlife from Poaching?
b) Why is it important to preserve the major hotspots and how do they contribute to the
Environment in different ways?
5. a) Describe various Air pollutants and their characteristics.
b) Discuss the various Air pollution control measures.
6. a) What are the major causes of Nuclear hazards and accidents?
b) Discuss the ways to minimize radiation exposure in case of a nuclear accident.
7. Explain the trends with regard to the populous countries in the world and their
environmental implications and the control measures to be adopted.
8. Describe your recent visit to any cosmopolitan city and its impact on environment and
discuss the various measures to control the pollution levels.
1 of 1
SET - 3
Code No: V0122
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
ENVIRONMENTAL STUDIES
(Common to CE, EEE, ME, CSE, EIE, BME, IT, E.Con.E, BOT)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Explain the need for students from all courses to be aware of environmental issues.
b) Write briefly about the scope of environmental studies.
2. a) Compare and Contrast between Renewable and Non-Renewable resources.
b) Explain the Environmental impact of extracting and using Mineral resources.
3. a) Define an ecosystem and list various components of an ecosystem.
b) Briefly explain the manner in which ecosystems are destroyed by human activities.
4. a) How do you explain Biodiversity at Global, National and Local levels?
b) Discuss about various Ex-Situ conservation measures of Biodiversity.
5. a) Discuss about the wastes that are prohibited from processing along with municipal
solid waste.
b) Briefly describe methods of heating and disposal of solid waste.
6. a) What is global warming? Enumerate the steps being taken to reduce the effects of
Global Warming.
b) How do you create Public awareness for protection of Environment?
7. a) Explain the trends with regard to the populous countries in the world and their
environmental implications.
b) Discuss the role of Family Welfare Programs in the control of population explosion.
8. a) Discuss about any three alternative energy sources and compare with conventional
energy sources.
b) Explain in detail about utilization of solar energy for water heating and street lights.
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
POWER SYSTEM - I
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Draw the schematic diagram of a modern thermal power station and explain its operation
2 a) Discuss various factors associated with rapid growth of nuclear power industry
b) Describe the construction and use of nuclear reactor core
3 a) Discuss briefly various electrical distribution systems
b) A D.C. two-wire distributor of length 1000 m is loaded uniformly at 2 A/m run. The
distributor is fed at one end at 220 volt. Determine (i) the voltage drop at a distance 250m
from the feeding station and (ii) voltage drop at the far end. The loop resistance is 3x 10-5
W/m.
4 . A single-phase distributor has loop resistance of 0.3 W and a reactance of 0.4W. The far end
of the distributor has a load current of 100A and a power factor 0.8 lagging at 220 V. The
midpoint Q of the distributor has a load current of 50 A at power factor 0.9 lagging with
reference to voltage Q. Determine the sending end voltage and power.
5 a) What are the merits and demerits of indoor substations over outdoor substations?
b) Briefly discuss the classification of substations
6 a) Explain the function of a synchronous phase modifier placed at the receiving end of the
transmission line
b) A 3-Phase, 50 Hz, 3000 V motor develops 600 HP, the p.f being 0.75 lagging and the
efficiency 0.95. A bank of capacitors is connected in delta across the supply terminals and
the p.f raised to 0.98 lagging. Each of the capacitance units is built of five similar 600 V
capacitors. Determine capacitance of each capacitor
7 a) Explain the significance of daily load curve
b) A central station supplied energy to two sub – stations A and B; Four feeders take off
from each of the sub-stations. The maximum demands are as given below.
Central station: 10 MW
Sub station A: 6 MW
Sub station B: 8 MW
Feeders on substation A: 1.50, 2.0, 5.0, 3.0 MW
Feeders on substation B: 2.0, 4.0, 5.0, 1.0 MW
Calculate the diversity factors between
(i) Sub stations, (ii) Feeders on sub stations A and (iii) Feeders on substation B.
8 a) Explain the various costs of electrical energy
b) Calculate the number of units to be consumed so that the annual bill on the basis of two
part tariff is same for the following data
Maximum demand = 15 kW
Two – part tariff Rs.1,000 per annum per kW of maximum demand plus Rs. 1.6 per unit
consumed. Flat rate tariff Rs. 2.5 per unit
SET - 1
Code No: T0221
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
POWER SYSTEM - I
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Explain the important components of a thermal power station
2. a) What is a nuclear reactor? Describe briefly various components of a nuclear reactor
b) Draw the schematic diagram of a nuclear power station and discuss its operation
3. a) Discuss the relative merits and demerits of DC distribution and AC distribution systems.
b) A two-wire distributor is fed at F1 and F2 at 230 V and 220 V respectively. Loads of 150
A and 100 A are taken at points P and Q. Resistance of both the conductors between F1P is
0.03W, between PQ is 0.05W and between QF2 is 0.02W. Determine the current in each
section of the distributor and voltage at each load point.
4. A single phase line (PQR) of length 3 km has resistance and reactance (go and return) as
0.05 and 0.2 ohms / km. P is the feeding point, Q is the mid point of the line taking a load of
50A at 0.707 p.f. lag and R is the far end taking a load of 100 A at UPF. The voltage at the
far end R is 230V. Determine the voltage at the sending end and the phase angle difference
between the voltages of two ends. If
i) power factors of the loads are with reference to far end voltage
ii) power factors of the loads are with reference to the voltages at the load points.
5. a) Briefly discuss the classification of substations
b) Explain the single bus bar system with sectionalization and list their merits and
demerits
6 a) Describe ‘off load’ and ‘on load’ tap changing transformers
b) A 3 phase, 50 Hz, 400 V motor develops 100 H.P., the p.f. being 0.7 lag and efficiency
93%. A bank of capacitors is connected in delta across the supply terminals and p.f. is raised
to 0.95 lag. Each of the capacitance units is built of 4 similar 100 V capacitors. Determine
the capacitance of each capacitor.
7 a) Discuss the difference between load curve and load duration curve
b) A certain power station annual load duration curve is a straight line from 20 MW to
7MW. To meet this load, three turbine-generator units, two rated at 12 MW each and one
rated at 8 MW are installed. Calculate the following
(i) Installed capacity
(ii) Plant factor
(iii) Units generated per annum
(iv) Utilization factor
8 a) What are the factors influencing the formulation of tariff
b) The data of a power station as follows:
Installed capacity =200 MW
Capital cost = Rs. 350 × 106
Rate of interest and depreciation = 20%
Annual cost of fuel oil, salaries and taxation = Rs. 40 × 106
Load factor = 0.5
Determine the cost of generation and cost of saving per kWh if the annual load factor is
raised to 0.6.
SET - 2
Code No: T0221
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
POWER SYSTEM - I
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a) Discuss various factors which affects the selection of site for a thermal power plant
b) Describe with a neat sketch the construction, principle of operation and application of an
economizer
2. Draw a typical layout of a gas turbine power plant and describe the function of different
components of this plant
3 a) Prove that the total voltage drop in a uniformly loaded distributor fed at one end is equal
to the drop produced by the whole load assumed contracted at the midpoint of the distributor
b) A D.C. two wire distributor F1F2 is fed at both ends at the same voltage of 220 Volt. The
length of the distributor is 250 m and the loads tapped off from the end F1 are:
Distance in meter: 50 75 100 150
Load in amps : 10 40 30 25
The resistance per kilometer of both distributors is 0.2 ohms. Find (i) the current in each
section and (ii) the voltage at each load point.
4. A 3 - phase ring distributor PQRS, fed from the end P at 11 kV, supplies balanced loads of
40 A at 0.85 pf lag at Q, 60A at 0.8 pf lag at R and 50a at UPF at S, the load currents being
referred to the voltage at P. The impedances of the sections PQ, QR, RS and SP are
(3+5j),(2+j2), (4+j5) & (1+j3) W respectively. Calculate the currents in various sections and
bus bar voltages at Q,R and S
5. a) What are the merits and demerits of GIS substations
b) Explain the main and transfer bus bar system with circuit diagram
6. a) Why voltage control is required in power systems? Mention the different methods of
voltage control employed in power system
b) A single phase system supplies the following loads
i) Light load of 50 kW at unity power factor
ii) Induction motor load of 125 kW at p.f. 0.707 lagging
iii) Synchronous motor load of 75 kW at p.f 0.9 leading
iv) Other miscellaneous loads of 25 kW at p.f. 0.8 lagging
Determine the total kW and kVA delivered by the system and p.f at which it works
7 a) Explain the significance of load factor and diversity factor
b) Calculate diversity factor and annual load factor of a generating station supplies loads to
various consumers as follows:
Industrial consumer = 1500kW; Commercial establishment = 7500kW
Domestic power = 100kW; Domestic light = 400kW
And assume the maximum demand on the station is 2500kW and the number of units
produced per year is 40×105 .
8 a) What are the various types of tariff and explain the Two-part tariff method
b) A customer takes a constant load of 200kW at a p.f. of 0.85 lagging for 12 hours per day
and 365 days per annum. Calculate the annual payment under each of the following tariffs.
(i) Rs.1.3 per kWh + Rs.1,000 per kVA per annum
(ii) Rs.1.25 per kWh + Rs.1,000 per kW per annum + 30 paise per kVArh.
SET - 3
Code No: T0221
II B.Tech II Semester (R07) Regular/Supply Examinations, Apr- 2010
POWER SYSTEM - I
(Electrical and Electronics Engineering)
Time: 3 Hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. a ) Discuss and compare the performance of different types of boilers used in thermal power
plants
b) Explain with the help of a neat diagram, working of a feed water supply system
2 a) What is half period of a radioactive material and explain its significance
b) Explain clearly how the operation of nuclear reactor is controlled for generation of
electrical power
3 a) Compare underground distribution systems with over head distribution systems
b) A two wire 400 m long distributor is loaded as follows:
Meters from feeding point : 100 200 275 325 400
Load in ampere : 25 10 30 50 20
If the resistivity of conductor is 1.5 x 10– 8 W-m, what must be the cross-section of each
conductor, in order that the voltage drop may not exceed 10 volt.
4. A single phase two wire feeder 1 km long supplying a load of 50 A at 0.707 p.f lag. 35A at
0.8 p.f lag and 60 A at 0.9 p.f lag at distance of 250m, 500m and 1000m respectively from
the feeding end. The resistance and reactance of the feeder per km length are 0.05 and 0.2
ohms respectively of the voltage at the far end to be maintained 230V. Determine the
voltage at the receiving end voltage?
5 a) Compare air insulated substations with gas insulated substations
b) Explain the single bus bar arrangement with neat sketch and what are its merits as well as
demerits
6 a) Explain the method of improving power factor by using synchronous condenser. Discuss
its merits and demerits.
b) A single circuit 3-phase, 220kV, line runs at no load. Voltage at the receiving end of the
line is 205kV. Find the sending end voltage, if the line has resistance of 20 ohms, reactance
of 85 ohms and the total succeptance of 5.32×10-4 mho. The transmission line is to be
represented by Õ-model.
7 a) Define the following
(i) Load factor, (ii) demand factor, (iii) diversity factor, (iv) plant capacity factor and (v)
utilization factor
b) A power station is to feed four regions of load whose peak loads are 10MW, 5MW,
14MW and 6 MW. The diversity factor at the station is 1.3 and the average annual load
factor is 60%, determine the (i) maximum demand on the station (ii) Annual energy
supplied by the station and (iii)suggest the installed capacity.
8 a) Explain the various types of power factor tariff methods
b) A power station has got maximum demand of 40 MW with annual load factor is 60%.
Determine the cost per kWh generated from the following data:
Capital cost =Rs.80×105 , annual cost of fuel & oil = 5 Rs8×10 and taxes, wages & salaries
= 5 Rs5×10 and the rate of interest and depreciation is 12%
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