Basic Electrical Engineering (BEE) SPPU Endsem Question Paper May 2023

Questions

1. Q1

   1. a)

      Define impedance. Draw the impedance triangle for R-L & R-C series circuit.

      [4]
   2. b)

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

      [6]
   3. c)

      The series circuit having resistance 10  , inductance 0.1 H and capacitance 150 μ F is connected to 1-phase, 200 V, 50 Hz AC supply, Calculate - i) Inductive reactance Xl ii) Capacitive reactance Xc iii) Net reactance X iv) Impedance Z v) Current drawn by the circuit vi) Power factor vii) Active power P viii) Reactive power Q.

      Also asked:Jan 2026 ·Nov 2025

      [8]
   OR

2. Q2

   1. a)

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

      [4]
   2. b)

      Derive the expression for power, when voltage v = Vm sin ω t is applied across R-L series circuit.

      [6]
   3. c)

      The series circuit having resistance 10  and capacitance 150 μ F draws a current of 9.4 A from 1-phase, 50 Hz AC supply. Calculate - i) Capacitive reactance ii) impedance iii) power factor iv) supply voltage v) Active power and vi) reactive power.

      [8]

3. Q3

   1. a)

      Define i) Balanced load ii) Unbalanced load and iii) Phase sequence.

      Also asked:Nov 2025

      [3]
   2. b)

      Derive the EMF equation of single phase transformer.

      Also asked:Jan 2026 ·Nov 2025 ·May 2025 ·May 2024 ·Nov 2023

      [6]
   3. c)

      Derive the relation between i) phase voltage and line voltage ii) phase current and line current in case of balanced STAR connected 3-ph inductive load. Assume phase sequence RYB. Draw the circuit diagram & necessary phasor diagram.

      Also asked:May 2025 ·May 2024

      [8]
   OR

4. Q4

   1. a)

      Define the voltage regulation and efficiency of transformer along with formula.

      [3]
   2. b)

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

      [6]
   3. c)

      Three identical impedances each of 6+j8  are connected in star across 3-ph, 400 V, 50 Hz ac supply. Determine. i) phase voltage ii) phase current and line current iii) power factor, 3-ph active, reactive and apparent power

      Also asked:Nov 2025

      [8]

5. Q5

   1. a)

      State and explain KCL & KVL

      [4]
   2. b)

      Calculate the current flowing through 4  (AB) for the circuit shown in fig 5b, using Kirchhoff ’ s Laws. All resistances are in 

      [6]
   3. c)

      Derive the equations to convert Delta connected resistive circuit into equivalent Star circuit.

      Also asked:Dec 2025

      [8]
   OR

6. Q6

   1. a)

      Explain the practical current source by means of i) Symbol of representation ii) Value of internal resistance iii) Graphs between V and I

      [4]
   2. b)

      Calculate the current flowing through 4  (PQ) for the circuit shown in fig 6b, using Superposition Theorem. All resistances are in  4

      [6]
   3. c)

      Calculate the current flowing through 4  (PQ) for the circuit shown in fig 6b, using Thevenin ’ s Theorem.

      [8]

7. Q7

   1. a)

      Define resistance of the material & state factors on which it depends.

      [3]
   2. b)

      Explain construction and working principle of Lithium ion battery.

      [6]
   3. c)

      Derive an expression for insulation resistance of a single core cable with the necessary diagram.

      Also asked:May 2025 ·May 2024 ·Nov 2023

      [8]
   OR

8. Q8

   1. a)

      State the material used for positive plate, negative plate & electrolyte for lead acid battery.

      [3]
   2. b)

      The current flowing at the instant of switching 240 V, 40 Watt lamp is 2 A. The TCR of tungsten filament is 0.0055 per degree Celsius at 20 º C. Determine. i) temperature of filament of the lamp ii) working current

      [6]
   3. c)

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

      [8]