EEC Importants Elements of Electrical Engineering Importants Questions for Msbte Exam

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Unit 1 

1.Draw series and parallel magnetic circuit.

2.Draw and explain Hysteresis Loop

3.State Fleming's right hand rule.Explain with neat diagram Lenz's law.State its any two applications

4.State Faraday's law of Electromagnetic Induction.

5.Compare electric and magnetic circuit on any four points.

6.Define each of the following terms:

(i)Magnetic flux

(B)Magnetic flux Density

(iii)Reluctance 

(iv)Permeability

(v)Field strength

(vi) Permeability

7. An iron ring of mean circumference of 90 cm is uniformly wound with 600 number of turns of wire.Calculate the value of flux density that a current of 1.5 A would produce in the ring. Assume relative permeability of 1400

8. A coil of 500 turns wound uniformly on an iron ring of mean circumference 50 cm and cross sectional arca of 4/p cm2,carries a current of 1 A.find(i) MMF(ii) Field strength(iii) Reluctance(iv)Flux Take mr-1000

Unit 2

1.Define form factor and peak factor for a Sinusoidal waveform

2.Define: 

(1)Time period

(ii)Frequency

(iii)Power factor

(iv)Phase difference

3.State value of power factor for purely resistive and purely capacitive circuit

Unit 3

1.Define phase sequence in 3 phase a.c.supply system.Write any four advantages of 3 Phase system over I Phase system.

2. Compare star and delta connection on basis

(i)Connection diagram

(ii) Neutral

(iii)Line and phase current

(iv)Line and phase voltage.

3.Draw star & Delta connected Load.State the relation between 

(i)Line voltage and Phase voltage.(ii)Line current and Phase current.

4.lf a 3 phase,400 V,50 Hz supply is connected to a balanced 3 phase star connected load of Impedance[3+j6]ohm per phase.Calculate(i)Phase current(ii)Phase voltage(iii) Power factor (iv)Total Active power(v) Reactive power

5.A 3 Phase balanced load contains R=12W and XC-15W in each phase.It is connected in star across a 230V,50Hz,3P-AC.

Calculate:- *Vph(i)Zpb(iii)Iph(iv)IL(v)pf(vi)P

6. Three similar coils each of resistance 20 and on inductance 0.1 H are connected in delta to a 3φ 440V,50 Hz supply system.Calculate the phase current,line current,phase voltage,line voltage,active power and reactive power.

Unit 4

1.State an emf equation of I phase transformer and write meaning of each term in an equation.

2.State and explain the different losses occurred in single phase transformer.Define efficiency of transformer.

3.Write principle of operation for a DC motor.Write two applications of (i)DC shunt(ii)DC series

4.Draw and label constructional diagram of D.C.Motor.State function of poles and brushes in DC motors. State material for each.

5. Compare between I phase Auto-transformer and two winding transformer. 10KVA,2200/200 V,50 Hz single phase transformer has 100 turns on secondary winding Calculate(1)Primary number of tums(ii) Full load primary current(iii) Full load secondary current(iv)Maximum value of flux in the core 

6. 1.5 KVA 230/110 V I phase transformer used in a laboratory. Calculate primary winding current.(i)Secondary winding current(ii)Tums ratio.(iii)Current ratio

Unit 5

1.Write any 4 applications of Stepper Motor. Suggest suitable motor for following applications-(1) Food Mixer(ii)Electric Fan

2.Draw schematic representation of single phase split phase type of Induction Motor and write its applications

3.Draw and label constructional diagram of Shaded Pole Induction motor.Write any two applications of it.

4.Why single phase Induction Motor is not self-starting How can it be made self-starting?

5.Draw and explain working principle of Universal Motor.How direction of rotation is reversed in it?Write any two applications of it

6.Draw a neat sketch of permanent capacitor If induction motor.Explain its working

Unit 6

1.Write & explain any four factors affecting an Earth Resistance.How to reduce Earth Resistance.

2.Explain the 4 points on importance of earthing.Write any four IE rules relevant to Earthing.

3.State the necessity of fuse.List the types of fuses. Write any four major points related to rewirable fuses.

4.Which are the different types of earthing?Draw and tabel any one type of Earthing.

5.Draw and explain the working principle of ELCB.Write any two applications of it.

6.Explain the working of fuse with neat diagram.

7.Write any two applications of each of the following 

(i)ELCB 

(ii)MCCB

(ii)MCB

(iv)Fuse