Code No: R21026
R10
SET - 1
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRONIC DEVICES AND CIRCUITS
(Com. to EEE, ECE, EIE, ECC, CSE, IT, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) Explain in detail about Magnetic Deflection in cathode ray tube.
b) The electron beam in a CRT is displaced vertically by a magnetic field of flux density
2 x 10-4 Wb/m2 .The length of the magnetic field along the tube axis is the same as that
of electrostatic deflection plates. The final anode voltage is 800v.Calcualte the voltage
whichshould be applied to the Y- deflection plates 1cm apart , to return the spot back to
centre of screen.
(7M+8M)
2.
a) Prove that the conductivity of a semiconductor is given by σ= q( p µp + n µp)
b) Define the terms conductivity and mobility in a semiconductor.
(7M+8M)
a) Draw the V-I Characteristic of Zener diode and explain its operation.
b) Explain Avalanche breakdown and Zener break down .
(7M+8M)
a) Obtain the ripple factor of a Full wave rectifier with shunt capacitor filter.
b) Compare the performance of inductive L-section and π-section filters.
(7M+8M)
a) Define α, β and γ of a transistor show how are they related to each other?
b) Explain how a transistor is used an amplifier.
(7M+8M)
3.
4.
5.
6.
a) Explain the characteristic parameters of the JFET
b) A JFET has a driven current of 4mA.If Dss = 8mA and Vgs(off)= - 6V. find the values of
Vgs and Vp.
(10M+5M)
7.
a) Explain in detail about Bias compensation method
b) Explain in detail about collector to base bias.
(7M+8M)
a) Derive the network parameters for Two port devices.
b) What are salient features of Hybrid Parameters?
(7M+8M)
8.
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Code No: R21026
R10
SET - 2
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRONIC DEVICES AND CIRCUITS
(Com. to EEE, ECE, EIE, ECC, CSE, IT, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) Explain in detail about electrostatic deflection in cathode ray tube.
b) An electrostatic CRT has a final anode voltage of 600V. The deflection plates are 3.5cm
long and 0.8 cm apart. The screen is at a distance of 20cm from the center of plates. A
voltage of 20V is applied to the defection plates.
Calculate i) Velocity of electron on reaching the field.
ii) Acceleration due to deflection field.
iii) Deflection produced on the screen in cm.
iv) Deflection sensitivity in cm/v.
(5M+10M)
2.
a) Explain the difference between intrinsic and extrinsic semiconductor
b) What is meant by p-type impurity in a semiconductor?
(8M+7M)
a) Draw the V-I Characteristic of PN junction diode and explain its operation.
b) Show that the Zener diode can be used as a voltage regulator.
(8M+7M)
3.
4.
A Half wave rectifier has a load of 3.5kΩ , If the diode resistance and secondary coil resistance
together have a resistance of 800Ω and input voltage has a signal voltage of peak value 240V
calculate i) Peak , average and rms valve of current flowing ii) dc power output
iii) ac power input iv) efficiency of the rectifier.
(15M)
5.
a) Explain the input and output Characteristic of a transistor in Common Emitter Configuration
b) Explain about punch through.
(10M+5M)
6.
a) With the help of suitable diagrams explain the working of different types of MOSFET.
b) Compare the MOSFET with JFET.
(10M+5M)
7.
a) Explain in detail about operating point and Basic stability
b) Explain in detail about compensation against variation in VBE , ICO.
8.
(8M+7M)
a) Why Hybrid parameters are called so? Define them.
b) A CE amplifier has the h-parameters given by hie = 1000Ω,hre = 2 x 10-4 , hfe =50
and hoe =25µ mho. If both the load and source resistance are 1k Ω, Determine the
i) Current gain ii) Voltage gain
(7M+8M)
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Code No: R21026
R10
SET - 3
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRONIC DEVICES AND CIRCUITS
(Com. to EEE, ECE, EIE, ECC, CSE, IT, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) Explain about in magnetic field.
b) A charged particle having charge thrice that of an electron and mass twice that of an electron
is accelerated through a potential difference of 50V before it enters a uniform magnetic
field flux density of 0.02 Wb/m2 at an angle of 25o with field.
Calculate i).The velocity of the charged particle before entering the field.
ii). Radius of the helical path
iii) Time of revolution.
(5M+10M)
2.
a) Explain about Fermi Level in between intrinsic and extrinsic semiconductor.
b) define Drift and diffusion currents in semiconductor.
(8M+7M)
3.
a) Explain the principle behind the Varactor diode and list out its applications.
b) Explain the Construction of a PIN diode and give the applications of PIN diode. (7M+8M)
4.
a) Explain about series and shunt voltage regulators.
b) Derive an expression for the ripple factor in a full wave rectifier using inductor filter.
(7M+8M)
a) A transistor has IB = 100µA and IC = 2µA Find
i) β of the transistor ii) α of the transistor iii) Emitter current IE
iv) if IB changes by +25µA and IC changes by +0.6mA. Find the new valve of β?
b) Explain about Photo Transistor.
(5M+10M)
5.
6.
7.
8.
a) Describe the working principle of an SCR with V-I Characteristics.
b) Briefly describe some applications of JFET.
a) Explain in detail about Stabilization factors.
b) Explain about Thermistor and Sensistor compensation.
(10M+5M)
(7M+8M)
a) Explain about Conversion formulas for the parameters of three transistor configuration
b) Explain in detail about Measurement of h-parameters
(7M+8M)
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Code No: R21026
R10
SET - 4
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRONIC DEVICES AND CIRCUITS
(Com. to EEE, ECE, EIE, ECC, CSE, IT, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
2.
a) Explain about Two – Dimensional motion of electron.
b) Explain in detail about Magnetic Focusing.
(7M+8M)
a) Discuss the following with respect to semiconductor
i) doping
ii) Dopant
iii) donor
iv) acceptor.
b) Explain “Majority and minority carriers” in semiconductors.
(8M+7M)
3.
a) What is tunneling? Form the energy band diagram explain the V-I characteristic of a
tunnel diode.
b) List out the applications of tunnel diode and mention its advantages and disadvantages.
(10M+5M)
4.
a) Draw the circuit diagram of an Half wave rectifier and explain its operation
b) Show that a Full wave rectifier is twice as efficiency as a Half wave rectifier.
(8M+7M)
5.
a) Explain the input and output Characteristic of a transistor in Common Base Configuration.
b) The Common Base d.c current gain of a transistor is 0.967 .If emitter current is 10mA,
What is the value of base current?
(10M+5M)
6.
a) Describe the working principle of an UJT with V-I Characteristics.
b) Explain why an SCR is operated only in the forward biased condition.
(8M+7M)
a) Explain about Self Bias Amplifiers.
b) Explain about Thermal runaway and Thermal stability.
(8M+7M)
7.
8.
a) Explain in detail about analysis of a transistor amplifier circuit biasing h - parameters.
b) Explain about Transistor Amplifier configurations.
(7M+8M)
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Code No: R21041
R10
SET - 1
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRICAL TECHNOLOGY
(Com. to ECE, EIE, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) State and explain Fleming’s right hand thumb rule.
b) Derive from first principles an expression for the emf of a DC generator.
2 a) How is a shunt motor started? Why it should not be started direct on line?
b) A 4-pole, lap wound DC motor has 540 conductors. Its speed is found to be
1000rpm.the flux per pole is 25mWb. It is connected to 230 Volts dc supply.
Armature resistance Ra is 0.8Ω. Calculate induced emf and armature current.
3 a) Derive an emf equation of a single phase transformer.
b) The maximum flux density in the core of 250/300V, 50Hz single- phase
transformer is 1.2 tesla. If the emf per turn is 8V. Determine primary and
secondary turns and area of core.
4
The following data were obtained on a 20kVA, 50 Hz, 2000/200V distribution
transformer:
Voltage (V) Current (A) Power (W)
OC test with HV open-circuited 200
4
120
SC test with LV short circuited 60
10
300
Draw the approximate equivalent circuit of the transformer referred to the HV
and LV sides respectively.
[5]
[10]
[6]
[9]
[7]
[8]
[15]
5 a) What are the advantages of three-phase induction motors over single-phase
motors? Also list their applications.
b) Draw and explain the torque-slip characteristics of an induction motor.
[7]
6
[15]
What is an alternator? Explain its principle of operation. With a neat diagram,
explain the constructional features of a three-phase alternator.
7 a) What are different types of single phase induction motors?
b) Explain the operation of a capacitor start, capacitor run induction motor.
8 a) Define and explain Deflecting torque, Controlling torque and Damping torque.
b) Compare between moving coil and moving iron instruments.
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[8]
[6]
[9]
[8]
[7]
Code No: R21041
R10
SET - 2
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRICAL TECHNOLOGY
(Com. to ECE, EIE, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) What are the types of DC generators? List their applications.
b) A 4-pole, lap wound, d.c 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.
2 a) What is back emf? Explain the significance of back emf.
b) A 10 kW, 250V, DC shunt motor with an armature resistance of 0.8ߗ and a
field resistance of 275ߗ takes 3.91A, when running at no-load at rated voltage
and rated speed. Calculate the machine efficiency as a generator when
delivering an output of 10kW at rated voltage and speed; and as a motor
drawing an input of 10kW.
3 a) Discuss the principle of operation of a single-phase transformer.
b) What are different types of single-phase transformers? Explain its
constructional features.
4
The efficiency of a 1000 kVA, 110/220V, 50Hz, single-phase transformer is
98.5% at half full-load at 0.8 pf leading and 98.8% at full-load upf.
Determine: i) iron loss , ii) full-load copper loss, and iii) maximum efficiency
at upf.
[7]
[8]
[6]
[9]
[7]
[8]
[15]
5 a) List and explain different types of induction motors. Mention few applications
of induction motors.
b) Explain the rotor resistance starting scheme for a slip-ring induction motors.
[8]
6 a) Define and explain pitch factor and distribution factor.
[6]
b) Derive the expression for emf induced in an alternator.
[9]
7 a) What are different application of single-phase induction motors
8
[7]
[6]
b) Explain in detail the operation of a shaded-pole single-phase induction motor.
[9]
With a neat diagram, explain the operation of a permanent magnet moving
coil instruments. Also mention its applications.
[15]
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Code No: R21041
R10
SET - 3
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRICAL TECHNOLOGY
(Com. to ECE, EIE, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) Explain with a neat sketch, the constructional details of a DC machine.
b) A DC generator is found to develop an armature voltage of 200 V. If the flux
is reduced by 25% and speed is increased by 40%, calculate the armature
generated voltage.
2 a) What are different losses that occur in a DC motor? Explain briefly.
[9]
[6]
[6]
b) A 4-pole DC motor is lap-wound with 400 conductors. The pole shoe is 20 cm [9]
long and average flux density over one-pitch is 0.4T, the armature diameter
being 30 cm. Find the torque and gross mechanical power developed when the
motor is drawing 25A and running at 1500 rpm.
3 a) With a phasor diagram, explain the operation of a single phase transformer on
no-load condition.
b) Define and explain the terms: step-up transformer, step-down transformer,
ideal transformer and isolated transformer.
[7]
4
What are different losses that occur on a transformer? Explain the conduction
of open-circuit and short-circuit tests on transformers.
[15]
5
List and explain in detail different starting methods for a three-phase
induction motor.
[15]
6 a) What are different types of alternators?
[8]
[5]
b) A 3-phase, 16 poles alternator has a star-connected winding with 144 slots and [10]
10 conductors per slot. The flux per pole is 0.03 Wb, sinusoidally distributed
and the speed is 375 rpm. Find the frequency of generated voltage, the
magnitude of phase voltage and lone voltage. Assume full-pitched coil.
7 a) Explain the working of an AC servomotor. Also list their applications.
b) What are stepper motors? List different types of stepper motors.
8 a) List the advantages and limitation of permanent magnet moving coil
instruments.
b) A PMMC instrument has a coil resistance of 100Ω and gives a fullscale
deflection (FSD) for a current of 500 µA. Determine the value of shunt
resistance required if the instrument is to be employed as an ammeter with a
FSD of 5A.
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[8]
[7]
[7]
[8]
Code No: R21041
R10
SET - 4
II B. Tech I Semester Supplementary Examinations, June - 2015
ELECTRICAL TECHNOLOGY
(Com. to ECE, EIE, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) What is residual magnetism? Explain its use.
b) A 4–pole, lap wound 750 rpm DC shunt generator has an armature resistance
of 0.4Ω and field resistance of 200Ω. The armature has 720 conductors and
the flux per pole is 30m Wb. If the load resistance is 15Ω, determine the
terminal voltage.
2 a)
Discuss a scheme to control the speed of a DC motor above its rated speed.
b) Explain the operation of the three point starter with neat sketch.
[6]
[9]
[7]
[8]
3 a) What is a transformer? Differentiate between a core-type and a shel-type
transformer.
b) State and prove the condition for maximum efficiency of a transformer.
[8]
4
[15]
A 100KVA, 1-phase transformer has full load primary current of 400A and
total resistance referred to primary is 0.006. If the iron loss amounts to 500W,
find the efficiency at full load and half load at
i) Unity power factor
ii) 0.8 power factor.
5 a) Compare between Slip ring and Squirrel cage induction motors.
b) Define and explain the terms: slip and slip speed of an induction motor.
6
[9]
[6]
What is regulation? Explain the predetermination of regulation of an alternator [15]
by Synchronous Impedance Method
7 a) What is a tachometer? Explain the operation of AC tachometer.
b) What is a synchro? What is the primary purpose of a synchro system? What
are the two major components of a synchro?
8
[7]
Explain in detail the construction and basic principle operation of Movingiron Instruments. Also mention its applications.
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[8]
[7]
[15]
Code No: R21022
R10
SET - 1
II B. Tech I Semester Supplementary Examinations, June - 2015
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Com. to EEE, ME, ECE, EIE, CSE, IT, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) “Managerial Economics is the integration of economic theory with business practice for
the purpose of facilitating decision making and forward planning by management”.
Explain?
b) Define demand and describe its determinants with suitable examples?
2.
a) Differentiate between the following:
i) Point Price elasticity of demand and Arc Price elasticity of demand
ii) Elasticity of demand and elasticity of supply
b) Write briefly about trend projection method?
3.
a) What is the relationship between firm’s short run production function and its fixed and
variable costs?
b) Distinguish between:
i) Implicit and Explicit costs
ii) Accounting and Economic costs
4.
a) What are the features of Perfect competition?
b) Distinguish between Market skimming pricing and penetrating pricing.
5.
a) What are the features of Joint stock Company?
b) Write short note on features of Business cycles.
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R10
Code No: R21022
6.
SET - 1
The following are the balances extracted from the books of Rakesh on 31st March 2015.
PARTICULARS
Rakesh Capital
Rakesh Drawing
Furniture and Fixtures
Opening Stock
Debtors
Rent from tenants
Purchases
Sales
Electricity Charges
Sales return
Discounts (Dr)
Bank Overdraft
Creditors
Discount (Cr)
Taxes and Insurances
General Expenses
Salaries
Commission (Dr)
Carriage on purchases
Bad debts
AMOUNT (IN RUPEES)
30,000
5,000
2,600
22,000
18,000
1,000
1,10,000
1,50,000
1,100
2,000
1,600
4,200
13,800
2,000
2,000
4,000
9,000
2,200
1,800
800
Adjustments:
Closing stock at the end was Rs 20,060; Depreciate furniture and fixtures by Rs 550.
Prepare Trading, Profit and Loss account and Balance Sheet for the year ended 31st March
2015 after taking the above adjustments.
7.
From the following particulars you are required to prepare a statement of proprietary fund:
Capital turnover ratio=2; Fixed Asset turnover ratio=4; Gross profit turnover ratio=20%; Stock
velocity=5; Debtors velocity= 3 months; Creditors velocity is 2.5 months. The gross profit is
Rs 50,000,Reserves and Surplus is Rs 15000 and closing stock was Rs 5000 lesser than
opening stock.
8.
Explain briefly the various methods of capital budgeting.
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Code No: R21022
R10
SET - 2
II B. Tech I Semester Supplementary Examinations, June - 2015
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Com. to EEE, ME, ECE, EIE, CSE, IT, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1.
What do you understand by Elasticity of demand? How do you measure it? What is its
significance?
2.
Explain and illustrate the following: and also mention why they arise: a) The Law of Constant
Returns b) The Law of increasing returns.
3.
What is opportunity Cost? Give some examples of opportunity cost. How are these costs
relevant for managerial decisions?
4.
What is a Market? Explain, in brief, the different Market structures.
5.
Explain the merits and demerits of different forms of Business organization and their suitability
with different types of business Activities
6.
What are the accounting concepts that govern accounting process? Explain in brief.
7.
The following are the extracts from the financial statements of Marvel Ltd. as on 31st March
2014 and 31st March 2015 respectively
31st March 2014
31st March 2015
( Amount in Rupees) ( Amount in Rupees)
Stock
10,000
25,000
Debtors
20,000
20,000
Bills receivable
10,000
5,000
Cash
18,000
15,000
Bills payable
15,000
20,000
Bank Overdraft
2,000
9% Debenture
5,00,000
5,00,000
Sales
3,50,000
3,00,000
Gross Profit
70,000
50,000
Compute Current ratio, Acid test ratio and Stock Turnover ratio and also interpret the result.
8.
Compare and contrast with illustration
Accounting rate of return and Payback period method
Net present Value and IRR method
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Code No: R21022
R10
SET - 3
II B. Tech I Semester Supplementary Examinations, June - 2015
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Com. to EEE, ME, ECE, EIE, CSE, IT, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1.
Define Managerial Economics. Explain the nature and scope of managerial economics?
2.
What is meant by Elasticity of demand? What are the factors governing the potential demand
for a product as either Elastic or Inelastic?
3.
Explain how production function is valuable to manufacturer?
4.
What are the features of perfect competition? Explain with the help of a diagram how price
output is determined in perfect competition?
5.
Define and evaluate partnership form of business organization.
6.
What is working capital? What are the factors governing working capital requirement?
Illustrate.
7.
Ram Enterprise is considering purchasing a CNC machine. The following are the earnings after
tax from the two alternative proposal under consideration each costing Rs 8,00,000. Select the
better proposal if the company wishes to operate @ 10% rate of return
Year 1
Year 2
Year 3
Year 4
Year 5
Proposal I
80,000
2,40,000 3,20,000 4,80,000 3,20,000
Proposal 2
2,40,000 3,20,000 4,00,000 2,40,000 1,60,000
Present value of Rs 1 @10%
0.909
0.826
0.751
0.683
0.620
8.
Journalize the following transactions and post them to ledger.
i) Ram invested Rs 10,000 in cash
ii) He bought goods worth Rs 2000 from Shyam
iii) He bought a machine for Rs 5000 from Lakshman on account
iv) He paid to Lakshman Rs. 2000
v) He sold goods for cash Rs. 3000
vi) He sold goods to A on account for Rs 4000
vii) He paid to Shyam Rs. 1000
viii)He received amount from A Rs. 2000.
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Code No: R21022
R10
SET -4
II B. Tech I Semester Supplementary Examinations, June - 2015
MANAGERIAL ECONOMICS AND FINANCIAL ANALYSIS
(Com. to EEE, ME, ECE, EIE, CSE, IT, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~~
1. a) What do you understand by demand? What are the different types of demand
b) State the law of demand what its exception are
2. How do you forecast demand for product and services? Explain the method of least squares as a
method of forecasting demand.
3. Do you think monopoly is present in the current business environment? Explain how price
output is determined in monopoly in short run
4. Rahim sells 500 kg of sweets per hour at a rate of Rs 100 per kg. The fixed overhead is Rs 7000
and the variable cost is Rs 25 per kg. There is a proposal to reduce the price by 10%.Calculate
the present PV and present BEP both in units and in Rupees; present level of profit and future
PV ratio and BEP both in units and in Rupees. How many kilograms must be sold to earn
present level of profit?
5. Explain any four pricing methods based on strategy.
6. Based on the following information of the financial ratios prepare Balance sheet of Premier
India Ltd as on 31st March 2015.
Current ratio= 2.5; Liquidity ratio= 1.5; Net working Capital= 6,00,000; Stock turnover ratio=
5; Gross profit to sales =20%. Turnover ratio to net fixed assets (on cost of sales) =2; Average
debt collection period = 2.4 months; Fixed asset to net worth =0.8; Long term debt to capital
and Reserves =7:25.
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Code No: R21022
SET -4
R10
7. From the following prepare Trading, Profit and loss and Balance Sheet as on 31st March 2015.
Particulars
Capital
Purchases
Sales
Carriage Inwards
Wages outstanding
Plant
Depreciation on plant
Rent received
Salaries and wages
Reserve for bad and doubtful debt
Bad debts
Interest
Premises
Interest paid
Creditors
Opening stock
Loans
Debtors
Debit
Credit
20000
29000
55000
5000
2000
20000
4000
1000
3000
1000
2000
5000
20000
5000
6000
25000
38000
15000
Adjustment
Closing stock at the end: Rs 40,000
Depreciate building at the rate of 15% per annum.
8. A ltd is considering to purchase a new machine costing Rs 5,85,000. An additional investment
will be required for installation costing Rs 15,000 and for working capital Rs 1,00,000. The
machine has a working life of 5 years and salvage value will be Rs 1,00,000. The working
capital will be released after 5 years. The estimated cash inflows before depreciation and tax are
estimated as follows
Years
Cash Inflows (Rupees)
1
1,00,000
2
1,80,000
3
2,50,000
4
2,00,000
5
1,50,000
You can assume straight line method for charging depreciation, cost of capital of 15% and
corporate tax rate of 50%. Should the company purchase the machine?
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RA
R13
Code No: PT21012
II B. Tech I Semester Supplementary Examinations, June - 2015
NETWORK ANALYSIS
(Electronics and Communication Engineering)
Time: 3 hours
Max. Marks: 70
Note: 1. Question Paper consists of two parts (Part-A and Part-B)
2. Answer ALL the question in Part-A
3. Answer any THREE Questions from Part-B
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PART –A
1
a) Define the ideal sources and draw their characteristics
b) Define the super mesh with diagram
c) Definition the Q and write its expression for series resonance
d) States the Milliman’s theorm
e) Write the basic equations for Inverse Transmission line parameters
f)
Define and obtain the time constant R-C circuit
PART -B
2
a) Definition the various terms associated with periodic functions
b) A Wheatstone bridge consists of AB= 5 ohms, BC = 7ohms, CD = 6 ohms and
DA = 5 ohms. A 10V cell is connected between A and C. Find the current through
galvanometer connected between B and D.
3
a) A circuit consists of a resistance of 15 ohm, a capacitance of 300 µF, and an inductor
of 0.06 H all in series. If supply of 240 V, 50 Hz is applied to the ends of circuit .
Calculate (i) current in coil, (ii) the potential difference across each element, and (iii)
the frequency at which current would have unity power factor.
b) Describe the super node and super mesh with suitable example
4
a) Two identical coils A and B, each having 3000 turns, lie in parallel planes such that
70% of the lines of force produced by one link the other. A current of 5 A in coil A
produces a flux of 0.06 mWb. If the current in the coil A changes from +8 A to – 8 A
in 0.05 sec, what will be the magnitude of the emf induced in B? Also, calculate the
self-inductance of each coil.
b) An impedance coil having a resistance of 10 ohm and inductance of 12 mH is
connected in parallel with a capacitor; find the value of this capacitor if the circuit
undergoes resonance when a 50 V, 230 Hz source is applied. Also determine the line
current under resonance.
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5
RA
R13
a) State and explain the compensation theorem
b) Determine the current through the 9-resistor for the following network using
superposition theorem below Figure 1.
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6
7
Find the Y-parameters of the circuit shown in below Figure 2.
a) Obtain the Laplace transform of useful functions
b) In the network shown in below Figure 3, the switch is closed at t = 0. Find the values
of i1(t) and i2 (t), assuming zero initial currents through inductors.
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Code No: R21042
R10
SET - 1
II B. Tech I Semester Supplementary Examinations, June - 2015
NETWORK ANALYSIS
(Com. to ECE, EIE, ECC)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1 a) Explain the classification of Network elements and give suitable examples for each
[8]
element.
b) Find the equivalent resistance for the circuit shown below across x – y.
[7]
2 a) Define and explain the following terms:
i)Root mean square value and ii) Average Value
b) Find the average and effective values of Saw tooth wave form shown below:
[7]
3 a) Derive the necessary equations for converting star connected resistances to delta
connected resistances.
b) In a series RL circuit the current and voltage are given as I = 4 cos (314t – 200) A,
V = 10 cos (314 t + 100)V. Find the values of R and L.
[8]
4 a) Explain the properties of resonance for a series RLC circuit
[7]
[8]
[7]
b) A coil having an inductance and resistance of 50 mH and 100 Ω is connected in series [8]
with a capacitor and a 100 V, 1K Hz Source. Obtain the value of capacitance that will
cause the resonance in the circuit. Find the circuit current at resonance frequency.
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Code No: R21042
5 a)
b)
R10
SET - 1
State and explain compensation theorem
[7]
Calculate the current in 4Ω resistor for the circuit shown below using Millman’s
[8]
theorem.
6
Obtain Z – Parameters and transmission parameters for the circuit shown below.
[15]
7 a)
What are the merits and demerits of Laplace transform
[8]
Given that current in the circuit at t = 0 is 5A. Obtain i(t) at t = 0+ for the figure
[7]
b)
shown below:
8 a)
b)
Analyze m – derived low pass filter.
[8]
Explain Band elimination filter
[7]
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Code No: R21042
R10
SET - 2
II B. Tech I Semester Supplementary Examinations, June - 2015
NETWORK ANALYSIS
(Com. to ECE, EIE, ECC)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1 a) State and explain Kirchhoff’s voltage and current Law
b) Determine the power supplied by the 10V battery for the network shown in below
figure
[8]
[7]
2 a) Define the following terms
i)Tree ii)Graph iii)node iv)Degree of a Node v)Link
b) A network is shown in the figure below: Draw its graph.
[8]
3
[15]
A circuit consists of a resistance of 15Ω, a capacitance of 300 µF and an inductor of
0.06H all in series. If the supply voltage is 240V,50 Hz applied to the ends of circuit.
Calculate i) current in the coil ii) Potential difference across each element iii) the
frequency at which the power factor is unity.
4 a) Explain the effect of resistance and inductance on the frequency response curve.
b) Find the value of R1 such that the given circuit in figure is resonant.
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[7]
[7]
[8]
Code No: R21042
R10
SET - 2
5 a) State and explain Norton’s theorem
b) Determine Norton’s equivalent circuit at terminals AB for the circuit shown in
figure below
[7]
[8]
6 a) Obtain open circuit parameters and loop equations of the network shown in figure
below:
[8]
b) Derive the relation between Z – parameters and ABCD parameters.
[7]
7
The following figure represents a parallel RLC circuit where R = 0.1Ω , L = 0.5 H
and C =1 F. Capacitor has an initial voltage of 10V with polarity shown in figure.
The switch K is closed at time t = 0. Obtain V(t)
[15]
8 a) What are Active and Passive filters? List the advantages of active filters over
passive filters.
b) A T- section low pass filter has series inductance 80 mH and shunt capacitance
0.022 µF. Determine the cut – off frequency and nominal design impedance.
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[8]
[7]
Code No: R21042
R10
SET - 3
II B. Tech I Semester Supplementary Examinations, June - 2015
NETWORK ANALYSIS
(Com. to ECE, EIE, ECC)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1 a) Define and explain the following terms:
[7]
i) Resistance ii) Inductance iii) Capacitance.
b) Find the equivalent capacitance across x-y.
[8]
2 a) Explain the principle of Duality
[7]
b) Draw the dual network for the circuit shown in figure below:
3 a) Explain the concept of complex Impedance and admittance
b) Explain the response of series RLC circuit for sinusoidal excitation.
4 a) Define coefficient of coupling (K) and explain the dot rule for coupled circuits.
b) In an ideal transformer, the mutual inductance is 10 H, number of primary and
secondary turns are 50 and 200. Obtain the value of primary current to produce 0.5
Wb flux to link with the secondary coil.
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[8]
[7]
[8]
[7]
[8]
Code No: R21042
R10
SET - 3
5 a) State and explain superposition theorem
[7]
b) Calculate the current across the 3 Ω resistor for the circuit shown below using super
position theorem and also calculate the power across 3Ω resistor.
6 a) Obtain the short circuit parameters for the network shown below:
b) Derive the relation between Z – parameters and Y – parameters.
7 a) Obtain the transient response of RL series circuit having DC excitation.
b) A series RL circuit having R = 25 Ω and L = 5H. A dc voltage of 100 V is applied at t
= 0. Find the equations for current and voltage across R and L.
8 a) Compare m –derived and prototype filters.
b) Design a m –derived low pass filter(T ) section having design resistance Ro = 500Ω,
cut – off frequency fc = 1500 Hz and infinite attenuation frequency fα = 2000Hz.
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[8]
[8]
[7]
[7]
[8]
[7]
[8]
Code No: R21042
R10
SET - 4
II B. Tech I Semester Supplementary Examinations, June - 2015
NETWORK ANALYSIS
(Com. to ECE, EIE, ECC)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1 a) Explain the different types of sources in detail
b) Find the source current for the circuit shown below:
2 a) Define form factor and peakl factor and also explain its significance.
b) Determine the form factor for the wave form given below:
[8]
[7]
[7]
[8]
3 a) Explain the phase relations for the i) pure resistor ii) pure inductor iii) pure capacitor
with phasor representations
b) Explain the response of parallel RLC circuit for sinusoidal excitation
[8]
4 a) Explain the difference between self inductance and mutual inductance
[7]
b) From the following data, find the self and mutual inductances of the two windings 1
and 2 of ideal transformers operating in a linear zone
N1 = 500 turns N2 = 750 turns I1 = 2A, Ø1 = 10mWb, Ø12 = 6mWb.
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[7]
[8]
Code No: R21042
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SET - 4
5 a) State and explain Norton’s theorem
b) Find the thevenin’s equivalent circuit for the network shown below:
[7]
[8]
6 a) Find Y –Parameters for the network shown below:
b) Derive the relation between Y –parameters and ABCD parameters.
[7]
7 a) Obtain transient response of RC circuit having DC excitation.
b) Calculate the time taken by a capacitor of 1 µF and in series with a 1MΩ resistance to
be changed up to 80 % of the final value.
[8]
[7]
8 a) Explain about the classification of filters, along with the characteristics of each type of
filter.
b) Design a Low pass filter.
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[8]
[7]
Code No: R21043
R10
SET - 1
II B. Tech I Semester Supplementary Examinations, June - 2015
PROBABILITY THEORY AND STOCHASTIC PROCESSES
(Electronics and Communications Engineering)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) Explain the term independent events and also write the properties of independent
events.
b) A binary communication channel carries data as one of the two types of
signals denoted by 0 and 1. Owing to noise a transmitted 0 is sometimes
received as 1 and a transmitted 1 is sometimes received as a 0. For a given
channel, assume a probability of 0.91 that a transmitted 0 is correctly received as a 0
and a probability of 0.94 that a transmitted 1 is received as a 1. Further assume a
probability of 0.4 of transmitting a 0. If a signal is sent, Determine
(i) Probability that a 1 was transmitted, given that a 1 was received
(ii) Probability that a 0 was transmitted, given that a 0 was received
5
2 a) Write the expressions for cdf and pdf of uniform and exponential random variables
and also sketch them.
b) Check whether the following function is a valid distribution function
GX(x) = 4[u(x-2a) - u(x-3a)]. Mention the properties used for justification.
5
c) Given k is a constant and X is a random variable with pdf
1
0 Find the value of c and P[1/2 < ¾]
3 a) Obtain the mean of Poisson random variable.
b) Define characteristic function of a random variable and write explain how moments
can be generated using it.
4 a) Define joint characteristic function and write its properties.
b) Two random variables X and Y have a joint probability density function
Check whether X and Y are statistically independent or not with supporting
expressions / values derived.
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4
6
8
7
5
10
Code No: R21043
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SET - 1
5 a) Define covariance of random variables X and Y and explain correlation coefficient.
b)
5
10
The density function of two random variables X and Y is
. Find the mean value of the function e–(X+Y).
6 a) State and prove any three properties of cross correlation function.
8
b) If a random process,
7
is given, where A and B are
2
uncorrelated zero mean random variables having the variance σ . Find autocorrelation
function of X(t).
7 a) Determine whether the following functions can be a valid power density function or
not? Support your claim with proper workout.
exp[-(ω-1)2]
b) State and prove Wiener-Khintchine relations
8 a) An LTI system is excited with a random process X(t). Obtain the expression for the
autocorrelation function of the response.
b) Write short notes on thermal noise.
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3
12
7
8
Code No: R21043
R10
SET - 2
II B. Tech I Semester Supplementary Examinations, June - 2015
PROBABILITY THEORY AND STOCHASTIC PROCESSES
(Electronics and Communications Engineering)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) Write the axioms of probability.
5
b) Two boxes B1 and B2 contain 100 and 200 light bulbs respectively. B1 and B2 have
10 and 5 defective bulbs respectively.
i) Suppose a box is selected at random and one bulb is picked out. What is the
probability that it is defective?
ii) Suppose we test the bulb and it is found to be defective. What is the
probability, which it came from B1?
2 a) A random variable X has the pdf
8
b) Define a random variable. Classify random variables and explain.
3 a) Obtain the mean of Gaussian random variable.
b) A random variable X is uniformly distributed on the interval (-4, 12). Another
random variable is defined as Y = e-X/4. Find E(Y).
4 a) Write the properties of joint distribution function.
b) Obtain the expression for pdf of sum of two statistically independent random
variables.
5 a) Prove that mean value of a weighted sum of random variables equals the weighted
sum of mean values.
b) Prove that any correlated Gaussian random variables are statistically independent
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7
8
7
5
10
8
7
Code No: R21043
R10
SET - 2
6 a) Check whether the random process X(t) = A cos(ωot +Θ) is WSS process or not, for
‘A’ and ωo being constant and Θ uniformly distributed between (0, π).
b) Explain the terms SSS process and Correlation ergodic process.
8
7
7 a) Determine whether the following functions can be a valid power density function or
not? Support your claim with proper workout.
+ + 1
b) Derive the expression for cross power density spectrum.
3
8 a) Write short notes on thermal noise.
7
b) Derive the expression for noise figure of a cascaded two port network.
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12
8
Code No: R21043
R10
SET - 3
II B. Tech I Semester Supplementary Examinations, June - 2015
PROBABILITY THEORY AND STOCHASTIC PROCESSES
(Electronics and Communications Engineering)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) With reference to mathematical modeling of experiments explain how is an
experiment defined mathematically.
b) An verification plan calls for verification of five chips and for either accepting each
chip, rejecting each chip, or submitting it for reverification, with probabilities of p1=
0.70, p2= 0.20, p3= 0.10 respectively. What is the probability that all five chips must
be reverified? What is the probability that none of the chips must be reverified?
c) Explain the terms continuous and discrete sample spaces
5
2 a) Write the expressions for cdf and pdf of Rayleigh and Poisson random variables and
also sketch them.
b)
Given the function
, find the value of b so that
gX(x) is a valid probability density.
5
c) Write the properties of CDF and explain.
3 a) Obtain the mean of Uniformly distributed random variable.
b) Find the characteristic function of the random variable with pdf 1/b( e-(X-a)/b). Also
find the first moment from it.
4 a) State and prove central limit theorem for equal distributions case.
b) Write the properties of joint density function.
6
4
4
6
8
7
10
5
5 a) The joint density function of two random variables X and Y is
10
Find the variances of X and Y.
b) Define joint characteristic function and write its properties.
5
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Code No: R21043
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SET - 3
6 a) Given that the autocorrelation function for a stationary ergodic process with no
periodic components is
Find the mean and variance of the process {X(t)}.
b) Explain the terms WSS process and Mean ergodic process.
7 a) Determine whether the following functions can be a valid power density function or
not? Support your claim with proper workout.
+ 1
b) Derive the expression for power density spectrum of a random process.
3
8 a) Write short notes on thermal noise.
8
b) Write short notes on average Noise figure.
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12
7
Code No: R21043
R10
SET - 4
II B. Tech I Semester Supplementary Examinations, June - 2015
PROBABILITY THEORY AND STOCHASTIC PROCESSES
(Electronics and Communications Engineering)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1 a) Explain the terms sample space, outcome, event and mutually exclusive events with
an example.
b) State and prove Baye’s Theorem.
7
2 a) Define conditional density and write its properties. Also discuss different methods of
defining the conditioning event obtain the respective density functions.
b) Write the expressions for cdf and pdf of Gaussian and binomial random variables and
also sketch them.
10
3 a) Obtain the mean of Binomial random variable.
8
b) Define moment function of a random variable and write explain how moments can be
generated using it.
4 a) The joint pdf of random variables X and Y is given b
Check whether X and Y are correlated or not.
b) Joint density function of random variables X and Y are given by
8
5
7
7
8
Find constant b so that this is a valid joint density function. Also find
5 a) Two random variables X and Y have joint characteristic function
7
Show that X and Y are zero mean random variables and uncorrelated.
b) For the transformations
where a, b, c, d are real
constants and X1 and X2 are random variables. Derive the expression for joint density
of Y1 and Y2 in terms of joint density of X1 and X2.
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8
Code No: R21043
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SET - 4
6 a) Prove that random process X(t)=A Cos(ωct+ ө) is a wide sense stationary process if it
is assumed that A, ωc are constants and Ө is uniformly distributed over interval
0≤ө≤2π.
b) Classify random processes and explain.
8
7
7 a) Determine whether the following functions can be a valid power density function or
not? Support your claim with proper workout.
+ 3 + 3
b) Derive the relationship between cross correlation function and cross power spectrum.
3
8 a) Write short notes on Narrowband random process.
8
b) Write short notes on Effective Noise Temperature.
7
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Code No: R21044
R10
SET - 1
II B. Tech I Semester Supplementary Examinations, June - 2015
SIGNALS AND SYSTEMS
(Com. to ECE, EIE, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a)Define and sketch the following signals
i) Signum Function
ii) Impulse function
iii) Unit step function
b) Define mean square error and derive the expression for evaluating mean square error
2. a) Find the Fourier series expansion of the half wave rectified sine wave shown below.
b) Find the even and odd components of the signal x(t)= sin t +cos t + cos t sint
3. a) Determine the fourier transform of the signal g(t)=A sinc2wt
b) Write a short notes of the following
i)Hilbert Transform ii)Modulation theorm
4. a) Find the impulse response of the system shown in figure 1 given below.Find the transfer
function.What would be its frequency response .Sketch its response .
b) List the properties of a LTI system and explain each property with an example.
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SET - 1
R10
Code No: R21044
5. a) If y(t)= x(t)* h(t) then show that x(t-t1) * h(t-t2) = y (t-t1-t2)
b) Derive an expression that relates energy spectral density and autocorrelation function.
6. a) The signal g(t)= 10 cos(20Пt)cos(200Пt) is sampled at the rate of 250 samples per
second. What is the Nyquist rate for g(t) as a low pass signal and determine the lowest
permissible sampling rate for this signal ?
b) State and explain sampling theorem for continuous signals?
7. a) Define Laplace transform and state the necessary conditions for its existence. List out its
advantages and disadvantages.
b) Determine the inverse Laplace transform of the following
i)
S 3 +1
S (S + 1)(S + 2)
ii)
S −1
(S + 1)(S 2 + 2S + 5)
8. a) The z-transform of a particular discrete time signal x(n) is expressed as
X (Z ) =
1 + 0.5Z −1
1 − 0.5Z −1
Determine the x(n) using the time shifting property1.
b) Explain the differentiation property of Z-transform?
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Code No: R21044
R10
SET - 2
II B. Tech I Semester Supplementary Examinations, June - 2015
SIGNALS AND SYSTEMS
(Com. to ECE, EIE, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) )A rectangular function f(t) is defined by
 1, 0 < t < π
f (t ) = 
− 1, π < t < 2π
Approximate this function by a wave form ‘Sin t’ over the interval (0,2П)such that the mean
square error is minimum.
b) Explain how a function can be approximated by a set of orthogonal functions.
2.
a) Consider the periodic square wave x(t) as shown in figure 1 given below.Determine the
complex exponential Fourier series of x(t).
b) State and prove the following fourier series properties.
i) Time Shift
ii) Frequency shift
3.
a) Determine the Fourier transform of the signal g(t)= 2 Sinc2wt
b) Find the Fourier Transform of Impulse function and Signum function
4.
a) How can you verify a system is distortion less and explain the same with required details?
b) List out the properties of a LTI system and explain each property with a relevant example.
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Code No: R21044
5.
SET - 2
R10
a) Compute the convolution sum y(n) to the following pair of sequences:
i) x(n)=y(n),h(n)= 2n u(-n)
1
2
ii) x(n)=(1/2)n u(n), h(n) = δ (n − 1)
b) State and prove convolution property of Fourier transforms.
6.
a) Discuss sampling of continuous time signals.
b) Find the Nyquist rate and Nyquist interval for the signal
x(t)=1/2 cos (4000Пt)cos(1000Пt)
7.
a) Discuss various properties of ROC’s for Laplace transform.
b) Determine the inverse Laplace transform of the following
8.
a) Determine the inverse Z-transform of the following X (z) by the partial fraction expansion
z+2
method. X ( z ) = 2
If the ROC’s are
2z − 7 z + 2
i) |z|>3
ii) |z|<1/2
iii) 1/2<|z|<3
b) Explain the differentiation property of Z-transform.
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Code No: R21044
SET - 3
R10
II B. Tech I Semester Supplementary Examinations, June - 2015
SIGNALS AND SYSTEMS
(Com. to ECE, EIE, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) Check whether the following signals are orthogonal or not
X1(n)=ejk(П/8)n and X2(n)= ejm(2П+/ П /8)n
b) A rectangular function f(t) is defined by
 1, 0 < t < π
f (t ) = 
− 1, π < t < 2π
Approximate this function by a wave form Sin t over the interval (0,2П) such that the mean
square error is minimum.
2.
a) State all the properties of Fourier series.
b) Derive the relationship between trigonometric and exponential Fourier series coefficients.
3.
a)Find the inverse Fourier transform of the following:
1
1
ii) X (w) =
i) X (w) =
2
a − jw
(a + jw)
b) Write a short notes of the following i)Hilbert Transform ii)Modulation theorem
4.
a) Draw the ideal characteristics of Low pass, High pass, Band pass and Band stop filters.
b) Test the linearity, causality, time variance, stability of the system governed by the equation.
i)y(n)=ax(n)+b
ii)y(n)=ncos[x(n)]
2
iii)y(n)=n[x(n)]
iv)y(n)=x(n)+nx(n-1)
5.
a) A system has an input x(t)= u(t) and H (w) =
1
. Find energy spectral density of the
(1 + jw)
output.
b) Find the convolution of the following signals x1 (t ) = e − t u (t ), x 2 (t ) = e 2t u (t.)
6.
a) Discuss different sampling techniques.
b) Explain the effect of under sampling aliasing.
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Code No: R21044
7.
R10
a) Define Laplace transform. Distinguish between Laplace transform and continuous time
Fourier transforms.
b) Find the output response y(t) of the RC low pass network as shown in the figure 1 given
below due to the input x(t ) = t e t / Rc u (t ) convolution.
8.
SET - 3
a) Determine the final value of the signal corresponding to the Z-transform
2z
X (z ) =
1 − 1.8 z −1 − 8 z − 2
b) Explain different properties of ROC of Z transform.
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Code No: R21044
R10
SET - 4
II B. Tech I Semester Supplementary Examinations, June - 2015
SIGNALS AND SYSTEMS
(Com. to ECE, EIE, ECC, BME)
Time: 3 hours
Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~
1.
a) Derive the condition for the two signals x1 (t ) and x 2 (t ) to be orthogonal to each other.
b) Define mean square error and derive the expression for evaluating mean square error
2.
a) Explain about Dirichlet’s conditions?
b) Explain the concept of complex Fourier spectrum with an example?
3.
a) Find the Fourier transform of the triangular pulse
 A (1 − t / T ) ; t > T
x(t ) = 
; t >T
0
b) State and prove the following properties of Fourier transform:
i) Multiplication in time domain
ii) Convolution in time domain
4.
a) What is an LTI system? Explain its properties.
b) Find the impulse response of the system shown in the Figure 1 given below. Find the
transfer function. What would be its frequency response? Sketch the response.
5.
a) Write short notes on cross correlation and its properties.
b) Find the power, rms value and sketch the PSD for the following signal.
X(t) = (A+sin100t)cos200t
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Code No: R21044
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SET - 4
6.
a)Determine the Nyquist rate for a continuous time signal
x(t)= 6 cos 50П t+20 sin 300П t+10 cos100Пt
b) Explain the following terms:
i) Natural sampling ii) Importance of sampling theorem
7.
a)State and prove initial and final value theorem wrt Laplace transform
b) Determine the Laplace transform of the following:
i) x(t)=sin(at) cos (bt)
ii) x(t)=Cos3 3t
iii) x(t)=t sinat
8.
a) Determine the inverse Z-transform of the following X(z) by the partial fraction expansion
method.
z+2
X (z ) = 2
2z − 7z + 2
If the ROC’s are
i) |z|>3
ii) |z|<1/2
iii) 1/2<|z|<3
b) Explain different properties of ROC of Z transform
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