Basic Electrical Engineering (BEE) SPPU Endsem Question Paper Dec 2025 (paper 2)

Questions

1. Q1

   1. a)

      Explain generation, transmission and distribution of electricity with the help of neat labelled single line diagram.

      [6]
   2. b)

      Find out current in 1 𝑜ℎ𝑚 resistance in fig. 1 by using Kirchhoff ’ s loop current analysis. Fig.1

      [6]
   OR

2. Q2

   1. a)

      Derive the equations to convert delta connected resistive network into equivalent star connected network.

      Also asked:May 2023

      [6]
   2. b)

      Find out current in 1 𝑜ℎ𝑚 resistance in fig. 1 by using superposition.

      [6]

3. Q3

   1. a)

      Compare electric circuit with magnetic circuit by mentioning their similarities & dissimilarities.

      [6]
   2. b)

      Two coils have 200 and 100 turns respectively wound on magnetic circuit with cross sectional area of 5 cm2. They have current of 2A and 0.5A flowing in it respectively and producing 1 mili-weber flux in each coil. The coefficient of coupling between them is 0.8. Calculate the self- inductance each coil and mutual inductance between them.

      [6]
   OR

4. Q4

   1. a)

      Define self-inductance in two ways. Also state the factors on which self- inductance depends.

      [6]
   2. b)

      Derive the expression for coefficient of coupling between two coils. SPPU QUESTION PAPER www.mysppu.in Page 1 MySPPU · Basic Electrical Engineering Page 1 of 3

5. Q5

   1. a)

      Define average value and derive an expression for average value of sinusoidal current in terms of its peak value.

      [6]
   2. b)

      An alternating current of pure sine wave has peak value 14. 14A and frequency of 50Hz. Find the instantaneous value of current at 4 milli-seconds and 8 milli-seconds. Also show these values on current Also show these values on current waveform.

      [6]
   OR

6. Q6

   1. a)

      Derive the mathematical expression for the current flowing through a pure capacitor when connected to an AC supply. Support your answer with: i) A neatly labelled circuit diagram ii) A phasor diagram iii) Waveforms of voltage and current

      [6]
   2. b)

      Single phase, 230V, 50Hz AC supply is connected to 30 milli-henry pure inductor. Draw circuit diagram and phasor diagram. Calculate. i) Inductive reactance ii) Current iii) Power factor iv) Power consumed

      [6]

7. Q7

   1. a)

      Draw impedance triangles for RL and RC series circuit. Also, express impedance in rectangular and polar form in both cases.

      [6]
   2. b)

      Single phase, 230V, 50Hz AC supply is connected to series circuit with resistance of 30 ohm and capacitive reactance of 40 ohm. Calculate i) Impedance ii) Current iii) Power factor angle iv) Power factor v) Power consumed. Also draw phasor diagram [6]

      [6]
   OR

8. Q8

   1. a)

      With the help of suitable circuit diagram and phasor diagram, derive relationship between line current and phase current in delta connected balanced R-L load supplied by symmetrical three phase AC supply.

      [6]
   2. b)

      Three phase, 400V, 50Hz AC supply is connected to star connected three phase load having series circuit consisting of resistance of 8 ohm and inductive reactance of 6 ohm in each phase. Calculate Impedance per phase, i) Phase voltage ii) Phase current iii) Power factor iv) Active power v) Reactive Power [6] SPPU QUESTION PAPER www.mysppu.in Page 2 MySPPU · Basic Electrical Engineering Page 2 of 3

9. Q9

   1. a)

      State different types of losses taking place in transformer along with mathematical equations, In which part do these losses take place. How these losses can be minimized.

      [6]
   2. b)

      A 5kVA, 3000V/200V, 50 Hz single phase transformer has cross sectional area of 150 cm2 for the core. If the number of turns of low voltage winding are 80, then calculate i) Number of turns of high voltage winding ii) Maximum value of flux density in core iii) Secondary full load current

      [6]
   OR

10. Q10

    1. a)

       Describe working principle of three phase induction motor by using rotating magnetic field theory. State two applications of squirrel cage induction motor and slip ring induction motor.

       [6]
    2. b)

       This part has equations that don’t show as text. Open the PDF to read it.

       [6]