Important RGPV Question, BT-104, BEEE, 1st Year

Important RGPV Question,

BT-104 BEEE, 1st Year

UNIT-1 D.C. Circuits

Q. 1) Find the voltage Vab in the network shown below.

Q. 2) Find the current through 6Ω resistor using Thevenin’s theorem.

Q. 3) Compute the power dissipated in 9Ω resistor using superposition theorem.

Q. 4) Using KVL and Thevenin’s theorem find the current in 3 Ω resistor of figure.

Q. 5) Determine the current in the branch AB using Superposition theorem.

Q. 6) State and prove Super position theorem.

Or

State and explain superposition theorem with the help of an example.

Or

Explain superposition theorem.

Or

State and explain superposition theorem.

Q. 7) Derive the relation for conversion for star and delta connection.

Or

Write short notes on Star Delta transformation.

Or

Explain delta/star and star/delta transformation.

Q. 8) Write short notes on Kirchhoff’s Law .

Or

State and explain Kirchhoff’s current and voltage law.

Or

State and explain KCL and KVL with suitable example.

Or

State and explain with neat diagram Kirchhoff’s laws for electrical circuits.

Or

Explain Kirchhoff’s current law and voltage law.

Or

Explain Kirchhoff’s law. 

Q. 9) Find the value of current in 10 Ω resistance for the following circuit using Kirchhoff’s law.

Q. 10) Compare the moving coil and moving iron instruments.   

Q. 11) Using Mesh analysis, find the current through the 5 Ω resistor for the network shown in figure.

Q. 12) Find the current through each resistor of the circuit shown in figure using superposition theorem.

Q. 13) Distinguish the voltage source and current source.

Or

Define voltage and current sources.

Q. 14) What do you understand by dependent and independent sources ? Explain with neat sketches.

Or

Distinguish between dependent sources and independent sources.

UNIT-2  1-Phase & 3-Phase AC Circuits

Q. 1) Define 3-phase balanced supply with phasor diagram.

Q. 2) Find the resistance RAB in the figure using star-delta transformation.

Q. 3) Draw Phasor diagrams of the following circuits.

i) Series R-L-C when XL > XC

ii) Series R-L-C when XL < XC

iii) Series R-L-C when XL = XC

Q. 4) A 3-φ balanced system supplies 110V to a delta connected load whose phase impedance is equal to (3.54 + j3.54) Ω. Determine the lie currents and draw the Phasor diagram.  

Q. 5) Discuss about the real power, reactive power, apparent power and power factor as regards to AC circuit.

Q. 6) If the power consumed in a 3φ, 220V, 50Hz supply What will be power consumed if the same load is connected in star. Also calculate the phase and line quantities of both the cases. The power factor of the load is 0.8 lagging.

Q. 7) Explain. (i) Apparent power (ii) Active Power (iii) Reactive power in a.c. circuit

Or

Explain in brief the active and reactive power.

Or

Define and explain active, reactive and apparent power.

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Write an introductory note on active, reactive and apparent power.

Or

What is active, reactive and apparent power in RLC series circuit ?

Q. 8) Draw Phasor diagram of a 3-phase star connected load and find the relation between phase and line voltages and currents.

Q. 9) A220, 100 Hz, A.C., source supplies a series RLC circuit with a capacitor and a coil. If the coil has 50 mH inductance, find at a resonance frequency of 100 Hz, what is the value of capacitor?

Q. 10) Draw Phasor diagram of a 3-phase star connected load and find the relation between phase and line voltages and currents.  

Q. 11) A delta connected load has a parallel combination of resistance (2Ω) and capacitive resistance (–j5Ω) in each phase. If a balanced three phase 440V supply is applied between lines, find the phase currents and line currents and the phasor diagram.

Q. 12) Explain the meaning of phase sequence and balanced and unbalanced supply and loads.  

Q. 13) Determine the power in balanced and unbalanced three phase system and their measurements.

Q. 14) Define the following with suitable diagram:

i) RMS values  ii) Form factor iii) Peak factor 

Q. 15) Derive an expression of impedance, current, power factor, power in watts, in R-LC series circuit.

Q. 16) A choke coil has resistance of 10 ohm and inductance of 0.05H is connected in series with a condenser of 100μf. The whole circuit has been connected to 200V, 50Hz supply. Calculate:  i) Impedance  ii) Current   iii) Power factor  iv) Real power

Q. 17) Explain how power in a 3 φ circuit can be measured by two wattmeter method.

Or

How is the power measured in 3-phase circuit ?

Or

Explain all the methods of 3-phase power measurement in balanced 3-phase circuit.

Q. 18) The power readings of two wattmeters are 15kw and -4kw for a 3-phase balance load. If the supply voltage is balanced 440V, find the true power drawn by the load, p.f. and line current.

Q. 19) Draw and explain the R-L-C series and parallel circuit.

Q. 20) Define the power factor.

Or

Define and explain power factor 

Q. 21) Explain the meaning and significance of the power factor of a circuit.

UNIT-3 Magnetic Circuits & Single Phase Transformer

Q. 1) Compare Electric and Magnetic circuit.

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Do the comparison of electrical and magnetic circuit on the basis of similarities and dissimilarities.

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Compare magnetic circuit with electrical circuit in detail.

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Explain the similarities and dissimilarities between electric and magnetic circuit.

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Distinguish between electrical and magnetic circuit.

Q. 2) Explain laws of Electromagnetic induction.

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State and explain the laws of electromagnetic induction.

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Explain laws of electromagnetic induction.

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Discuss the laws of electromagnetic induction.

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Explain Faraday’s law of electromagnetic induction.

Q. 3) Draw the typical normal magnetization curve of ferromagnetic material.  

Q. 4) Derive an expression for an energy density in magnetic circuits.

Q. 5) Discuss the construction, working principle, emf equation and equivalent circuit of single phase transformer.

Q. 6) The no-load ratio required in a single-phase 50 Hz transformer is 6600/600 V. If the maximum value of flux in the core is to be about 0.08 Wb, find the number of turns in each winding.

Q. 7) What are the necessary tests to determine the efficiency, voltage regulation and temperature rise of winding and insulation of transformer?

Q. 8) A 1100/400V, 50Hz single phase transformer has 100 turns on the secondary winding. Calculate the number of turns on its primary.

Q. 9) Explain different operating regions of a Bipolar Junction Transistor.

Q. 10) Enumerate the various losses in a transformer. How these losses can be minimized?

Or

What are the various losses in a transformer ? How can they be minimized ?

Or

Give reasons why core losses are called iron losses ?

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Describe in detail the losses in transformer.

Q. 11) Give reasons why rating of transformer is specified in kVA and not kW.

Q. 12) A transformer that with a 120 volt primary and 12 volts in the secondary and a primary with 900 turns of wire, how many turns would be required in the secondary?

Q. 13) Discuss about the magnetization characteristics of ferromagnetic materials.

Or

Discuss some of the magnetization characteristics of ferromagnetic materials.

Q. 14) A 6600/440V, single phase 600kvA transformer has 1200 primary turns. Find : i) Transformation Ratio    ii) Secondary turns   iii) Maximum flux through the core

Q. 15) Derive the expression for EMF of transformer. What is transformation ratio?

Or

What is meant by turn ration in transformer.

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What is voltage transformation ratio ? How is it related with current transformation ratio ?

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Derive an expression for induced e.m.f. in a transformer in term of frequency, the maximum value of flux and the number of turns on the windings.

Or

A coil wound on an iron core is excited from an A.C. source at voltage V(rms). Derive the expression for maximum flux in the core. Why is it independent of the core reluctance ?

Q. 16) Write a short notes on Voltage regulation and efficiency.

Q. 17) Explain induced E.M.F. and their types.

Q. 18) Write short notes on Equivalent circuit of a transformer

Q. 19) Explain open circuit and short circuit and short circuit test on a single phase transformer.

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How transformer is used for impedance transformation ? Explain the no load test used for the transformer parameter determination.

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Explain lab method to perform open circuit and short circuit test on single phase transformer.

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How transformer is used for impedance transformation ? Explain the no load test used for the transformer parameter determination.

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Explain the O.C. and S.C. test in transformer.

Q. 20) Discuss the principle working of single phase transformer.

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Explain the construction and classification of single phase transformer.

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Explain the principle of operation of transformer with suitable sketches.

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Explain the principle of working of single-phase transformer with the help of neat diagram indicating the flux.

Q. 21) Discuss in brief about the construction and basic principle of operation of transformer.

Or

Explain principle of working of a transformer. Explain core and shell type transformer with diagram.

Q. 22) Explain about open circuit and short circuit test.  

Q. 23) Open circuit and short circuit test on a single phase transformer gave the following results.  VO = 200V , IO = 0.7A, WO= 20 watt

Test from primary side, VS =10V, IS = 10A, WS = 40Watt Test from primary side Determine the equivalent circuit referred to primary side.

Q. 24) A 30kW, 33VDC shunt generator has armature and field resistance of 0.05 ohm and 100 ohm respectively. Calculate the total power developed by the armature when it delivers full output power.

Q. 25) Derive a relation that gives the value of force on a current carrying conductor.

Q. 26) What is hysteresis loop ? Explain it by drawing hysteresis loop.

Q. 27) Explain the procedure to analyse series magnetic circuit with air gap.

Q. 28) A single phase 50Hz, 250 V (primary) transformer has 80 turns on primary and 280 turns on secondary side. The area of core is 200 cm2. Calculate –

(i)            Maximum flux density on core

(ii)           Induced e.m.f. on secondary side.

UNIT-4 Electrical Machines

Q. 1) Describe the main parts of D.C. machines.

Or

Describe the constructional details of D.C. machine giving suitable diagram.

Or

Describe D.C. machine with neat sketches in viewing of main parts and constructional details.

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Describe the constructional details of D.C. machine giving suitable diagram.

Q. 2) With a neat diagram explain the working and principle of D C Motors.

Or

Write basic principle of operation and working of D.C. motor.

Or

Explain working principle of D.C. motor with necessary diagram. 

Q. 3) Derive the expression for generated voltage in D.C. machine.

Or

Derive e.m.f. equation of a D.C. motor/generator.

Or

Develop an e.m.f. equation for D.C. generator.

Q. 4) Explain in detail the Applications of DC Machines.

Q. 5) Give the reasons why starting current is high in D.C. motor ?

Q. 6) Explain the principle of operation of 3 – phase induction motor.

Or

Explain working principle of a 3-φ induction motor.

Or

Explain the concept of rotating magnetic field in a 3-phase induction motor.

Q. 7) Explain the construction and working principle of three-phase induction motor with suitable diagram.  

Q. 8) What is the difference between a separately excited and a self-excited generator?

Q. 9) An 8-pole DC machine has a wave winding containing 600 conductors. Calculate the generated e.m.f when the flux per pole is 0.08 Wb and speed is 215 rpm. If the flux per pole is-made 0.05 Wb. At what speed should the armature be driven to generate 500V.

Q. 10) A six pole lap wound D.C. generator as 720 conductors, a flux of 40mWb per pole is driven at 400 rpm. Find the generated e.m.f.

Q. 11) A 30 kW, 33 V D.C. shunt generator has armature and field resistance of 0.05 ohm and 100 ohm respectively. Calculate the total power developed by the armature when it delivers full output power.

Q. 12) Calculate the generated e.m.f. of a 8-pole wave wound D.C. generator which is having 720 conductors, flux per pole is 40mWb and is driven at 400 rpm.

Q. 13) Explain the torque-speed characteristic and speed control of separately excited DC motor.

Q. 14) Write short notes on Types of losses occurring in electrical machines.

Or

Write short notes Losses in electrical machines.

Or

Enumerate the various types of losses occurring in electrical machine.

Or

What are the common losses in a rotating machine and on what factors do they depends ?

Q. 15) Write the principle of operation of synchronous motor.

Or

What is the basic working principle of Synchronous machine.

Q. 16) What are the advantages of electromechanical measuring instruments ?  

Q. 17) With the help of meat sketches explain the construction and working principle of split phase induction motor.

UNIT-5 Basic Electronics

Q. 1) Simplify the Boolean function Z = AB+Ä€C+BC, therefore design the logic circuit using AND and OR logic gates.  

Q. 2) Explain the working of a diode and draw it V-I characteristics.

Or

Draw and explain voltage-current characteristics of P-N junction.

Or

Draw the V-I characteristics of germanium diode. Explain the same.

Or

Discuss V-I characteristic of P-N diode.

Q. 3) Explain the half and full adder circuits with their logic tables. (RGPV Jun 2020)

 

Q. 4) What are logic gates ? Enlist the different types of logic gates ?

Or

Write short note on logic gates. 

Q. 5) Write and explain truth table of-

(i) NAND gate

(ii) NOR gate

(iii) EX-OR gate 

Q. 6) Define transistor biasing.

Or

Discuss D.C. biasing of BJT.

Q. 7) Explain principle of operation and characteristics of BJT.

Or

Write short notes on BJT.

Or

What is transistor ? Explain the construction of transistor. 

Q. 8) Explain the working of bipolar junction transistor in common emitter configuration.

Or

Explain the working of transistor when it is operated in CE mode.

Or

Draw the connection diagram and explain the use and working of CE transistor configuration.

Q. 9) Explain how a transistor acts as switch? 

Q. 10) Explain the working of a full wave rectifier.

Q. 11) Draw and explain VI characteristics of diode.

Q. 12) Draw and explain the output characteristic of a NPN transistor operation in CE configuration.

Q. 13) Write short notes on  (a) Logic Gates (b) Half and full adder circuits

or

Explain the operation of half adder and full adder along with their logic diagram and truth table.

Or

Explain half adder and full adder with truth table.

Or

Explain the half adder and full adder.

Q. 14) Write a short notes on J-K flip-flop

Or

Explain the working principle of JK flip-flop.

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Explain the operation of JK flip-flop.

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With the help of circuit diagram, tables, explain the working of JK flip-flop. Explain race around condition in JK flip-flop.

Or

Draw and explain with the help of truth table working of JK flip-flop.

Or

Draw the truth table of JK flip-flop along with its logic diagram.

 

Q. 15) Write short notes on RS flip-flop

Or

Explain the operation of R-S flip-flop

Or

Explain the R-S flip-flop

 

Q. 16) Write short notes on IK flip-flop  

Q. 17) State and prove De-Morgan’s theorem and illustrate them using an example for each.

Or

State and explain De-Morgan’s theorem.

Or

State De-Morgan’s theorem with example.

Or

State and prove De-Morgan’s theorem using two variables.

Or

Write short notes on De-Morgan’s theorem.

Q. 18) Write short notes on :

a) Admittance

b) 2’s complement 

Q. 19) Differentiate between level and edge triggering. Draw the logic circuit an truth table for J K flip flop.

Q. 20) Explain how a BJT can be used as (i) An amplifier (ii) switch

— Best of Luck for Exam —

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