DC Circuits and Network Theorems MCQs 2026

111 questions with detailed answers · 36 from past papers · 12 quiz batches available

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Page 1 of 1 Questions 110 of 111
  1. Q1 Past Paper · PPSC/FPSC/CSS easy

    Kirchhoff Current Law at a node states that

    1. A sum of voltages is zero
    2. B sum of currents entering equals sum leaving
    3. C current is same in all branches
    4. D power is zero always
    💡 Explanation:

    KCL follows from conservation of charge.

  2. Q2 hard

    Wheatstone bridge P=100, Q=200, R=150 ohm; unknown S at balance is

    1. A 75 ohm
    2. B 300 ohm
    3. C 50 ohm
    4. D 450 ohm
    💡 Explanation:

    100/200 = 150/S → S = 300 ohm.

  3. Q3 Past Paper · PPSC/FPSC/CSS easy

    Kirchhoff Voltage Law around a closed loop states that

    1. A sum of currents is zero
    2. B algebraic sum of voltage drops is zero
    3. C sum of resistances is zero
    4. D current equals voltage
    💡 Explanation:

    KVL follows from conservation of energy.

  4. Q4 Past Paper · PPSC/FPSC/CSS easy

    Power dissipated in a resistor carrying current I is

    1. A I divided by R
    2. B R divided by I only
    3. C I times R only
    4. D I squared times R
    💡 Explanation:

    P = I²R = VI = V²/R for a resistor.

  5. Q5 Past Paper · PPSC/FPSC/CSS easy

    Conductance G of resistance R equals

    1. A R
    2. B R squared
    3. C 1/R
    4. D square root of R
    💡 Explanation:

    G = 1/R in siemens.

  6. Q6 Past Paper · PPSC/FPSC/CSS easy

    In a series circuit the current through each element is

    1. A inversely proportional to R always
    2. B the same
    3. C zero in largest R
    4. D divided equally by voltage
    💡 Explanation:

    Single path: same current everywhere.

  7. Q7 Past Paper · PPSC/FPSC/CSS easy

    In a parallel circuit the voltage across each branch is

    1. A proportional to branch resistance
    2. B always zero
    3. C the same
    4. D sum of branch voltages
    💡 Explanation:

    Parallel branches share the same potential.

  8. Q8 Past Paper · PPSC/FPSC/CSS medium

    A 100 W, 250 V lamp has hot resistance approximately

    1. A 2.5 ohm
    2. B 25 ohm
    3. C 2500 ohm
    4. D 625 ohm
    💡 Explanation:

    R = V²/P = 62500/100 = 625 ohm.

  9. Q9 Past Paper · PPSC/FPSC/CSS medium

    A 220 V, 1000 W heater resistance is approximately

    1. A 48.4 ohm
    2. B 220 ohm
    3. C 22 ohm
    4. D 484 ohm
    💡 Explanation:

    R = V²/P = 48400/1000 = 48.4 ohm.

  10. Q10 easy

    Balanced Wheatstone bridge galvanometer shows

    1. A zero deflection
    2. B maximum deflection always
    3. C unstable oscillation always
    4. D short circuit current
    💡 Explanation:

    Zero current in galvanometer at balance.

  11. Q11 easy

    Energy in a pure resistor is

    1. A stored in magnetic field
    2. B dissipated as heat
    3. C stored as charge permanently
    4. D converted to inductance
    💡 Explanation:

    Resistors dissipate; they do not store energy.

  12. Q12 easy

    A practical ammeter should have

    1. A very high internal resistance
    2. B infinite resistance
    3. C same R as voltmeter
    4. D very low internal resistance
    💡 Explanation:

    Low R minimizes loading error.

  13. Q13 easy

    Thevenin equivalent of a linear network is

    1. A voltage source Vth in series with Rth
    2. B current source only
    3. C single resistor only
    4. D capacitor in series
    💡 Explanation:

    Thevenin: Vth + series Rth.

  14. Q14 easy

    Norton equivalent of a linear network is

    1. A voltage source in parallel with R
    2. B short circuit only
    3. C current source In in parallel with Rn
    4. D open circuit only
    💡 Explanation:

    Norton: In || Rn.

  15. Q15 medium

    Thevenin voltage Vth is measured as

    1. A open-circuit terminal voltage
    2. B short-circuit current
    3. C load current at max power
    4. D internal drop only
    💡 Explanation:

    Vth = Voc at terminals.

  16. Q16 medium

    Thevenin resistance Rth is found by

    1. A adding all resistors always
    2. B measuring loaded voltage only
    3. C deactivating sources and looking into terminals
    4. D multiplying branch currents
    💡 Explanation:

    Zero sources; compute R at terminals.

  17. Q17 medium

    Norton current In equals

    1. A short-circuit terminal current
    2. B open-circuit voltage
    3. C Thevenin resistance
    4. D load current always
    💡 Explanation:

    In = Isc at terminals.

  18. Q18 medium

    For maximum power transfer to load, R_L should equal

    1. A Rth
    2. B zero
    3. C twice Rth always
    4. D half Rth always
    💡 Explanation:

    Max power when R_L = Rth.

  19. Q19 hard

    Maximum power when Vth=20 V and Rth=5 ohm with matched load is

    1. A 20 W
    2. B 100 W
    3. C 40 W
    4. D 10 W
    💡 Explanation:

    Pmax = V²/(4R) = 400/20 = 20 W.

  20. Q20 hard

    At maximum power transfer the efficiency is

    1. A 100 percent
    2. B 25 percent
    3. C 50 percent
    4. D 75 percent
    💡 Explanation:

    Half power in Rth, half in R_L.

  21. Q21 medium

    Superposition applies to

    1. A saturated magnetic cores only
    2. B nonlinear diodes only
    3. C linear bilateral networks
    4. D single-source circuits only
    💡 Explanation:

    Response = sum of individual source responses.

  22. Q22 medium

    When using superposition, other voltage sources are replaced by

    1. A open circuits
    2. B their load resistances
    3. C short circuits
    4. D infinite inductors
    💡 Explanation:

    Ideal voltage sources → shorts.

  23. Q23 medium

    When using superposition, other current sources are replaced by

    1. A short circuits
    2. B open circuits
    3. C Thevenin resistances
    4. D matched loads
    💡 Explanation:

    Ideal current sources → opens.

  24. Q24 medium

    Superposition cannot find directly

    1. A node voltage from one source
    2. B branch current from one source
    3. C total power in a resistor with multiple sources
    4. D Thevenin voltage
    💡 Explanation:

    Power is nonlinear in current.

  25. Q25 medium

    If Vth=12 V and Rth=4 ohm, Norton current is

    1. A 48 A
    2. B 0.33 A
    3. C 3 A
    4. D 8 A
    💡 Explanation:

    In = Vth/Rth = 3 A.

  26. Q26 medium

    Source transformation: V in series with R becomes current source

    1. A V times R in series
    2. B V/R in parallel with R
    3. C R/V in parallel
    4. D V in parallel with R only
    💡 Explanation:

    I = V/R with same R.

  27. Q27 hard

    Reciprocity theorem applies to

    1. A nonlinear networks only
    2. B unilateral devices only
    3. C magnetic saturation regions
    4. D linear bilateral networks
    💡 Explanation:

    Interchange excitation and response in linear bilateral nets.

  28. Q28 medium

    Mesh analysis uses

    1. A KCL at capacitors only
    2. B flux linkage only
    3. C only Ohm law at one node
    4. D KVL around independent loops
    💡 Explanation:

    Mesh currents + KVL per loop.

  29. Q29 medium

    Nodal analysis uses

    1. A KVL around every resistor
    2. B only Thevenin equivalents
    3. C KCL at nodes with voltage unknowns
    4. D magnetic flux balance
    💡 Explanation:

    Node voltages + KCL.

  30. Q30 medium

    Independent nodal equations for n nodes number

    1. A n
    2. B n plus 1
    3. C n squared
    4. D n minus 1
    💡 Explanation:

    One reference node at 0 V.

  31. Q31 hard

    Independent mesh equations for b branches and n nodes in planar net

    1. A n minus 1
    2. B b minus n plus 1
    3. C b plus n
    4. D b times n
    💡 Explanation:

    Independent loops = b - n + 1.

  32. Q32 medium

    A Wheatstone bridge is balanced when

    1. A all resistances equal only
    2. B galvanometer reads maximum
    3. C supply is zero
    4. D ratio of adjacent arms on one side equals the other
    💡 Explanation:

    Balance: P/Q = R/S.

  33. Q33 hard

    Delta to wye: each wye resistor equals

    1. A sum of two delta only
    2. B largest delta only
    3. C reciprocal of delta sum
    4. D product of two touching delta resistors divided by sum of all three delta
    💡 Explanation:

    Standard delta-wye transform.

  34. Q34 hard

    Three 6 ohm delta resistors convert to each wye arm of

    1. A 6 ohm
    2. B 18 ohm
    3. C 3 ohm
    4. D 2 ohm
    💡 Explanation:

    Ry = 6×6/18 = 2 ohm.

  35. Q35 medium

    Three 9 ohm delta to wye gives each arm

    1. A 9 ohm
    2. B 27 ohm
    3. C 1 ohm
    4. D 3 ohm
    💡 Explanation:

    Ry = 81/27 = 3 ohm.

  36. Q36 medium

    Voltage divider: R1 and R2 in series across V, voltage on R2 is

    1. A V times R1/(R1+R2)
    2. B V times R1/R2
    3. C V times R2/(R1+R2)
    4. D V always
    💡 Explanation:

    Series divider formula.

  37. Q37 medium

    Current divider: R1 parallel R2, total I, current in R1 is

    1. A I times R2/(R1+R2)
    2. B I times R1/(R1+R2)
    3. C I times R1/R2
    4. D I always equally
    💡 Explanation:

    Current splits inversely with R.

  38. Q38 hard

    Millman theorem combines

    1. A series capacitors only
    2. B parallel voltage sources with series resistances
    3. C delta networks only
    4. D magnetic cores only
    💡 Explanation:

    Single equivalent for parallel branches.

  39. Q39 hard

    Tellegen theorem relates to

    1. A power conservation in networks obeying KCL and KVL
    2. B resonance only
    3. C motor speed only
    4. D capacitive reactance only
    💡 Explanation:

    Topological power relation.

  40. Q40 hard

    Star-delta: each delta resistor from wye uses

    1. A simple sum of wye arms
    2. B product of all three wye
    3. C reciprocal sum only
    4. D sum of wye pair products divided by opposite wye arm
    💡 Explanation:

    Standard Y-delta conversion.

  41. Q41 easy

    A 6 V source drives 2 ohm load. Load current is

    1. A 12 A
    2. B 0.3333333333333333 A
    3. C 3 A
    4. D 8 A
    💡 Explanation:

    I = V/R = 3 A.

  42. Q42 easy

    A 10 V source drives 5 ohm load. Load current is

    1. A 50 A
    2. B 0.5 A
    3. C 15 A
    4. D 2 A
    💡 Explanation:

    I = V/R = 2 A.

  43. Q43 easy

    A 24 V source drives 8 ohm load. Load current is

    1. A 192 A
    2. B 0.3333333333333333 A
    3. C 32 A
    4. D 3 A
    💡 Explanation:

    I = V/R = 3 A.

  44. Q44 easy

    A 30 V source drives 10 ohm load. Load current is

    1. A 300 A
    2. B 0.3333333333333333 A
    3. C 40 A
    4. D 3 A
    💡 Explanation:

    I = V/R = 3 A.

  45. Q45 easy

    A 15 V source drives 5 ohm load. Load current is

    1. A 3 A
    2. B 75 A
    3. C 0.3333333333333333 A
    4. D 20 A
    💡 Explanation:

    I = V/R = 3 A.

  46. Q46 easy

    A 20 V source drives 4 ohm load. Load current is

    1. A 80 A
    2. B 5 A
    3. C 0.2 A
    4. D 24 A
    💡 Explanation:

    I = V/R = 5 A.

  47. Q47 easy

    A 12 V source drives 6 ohm load. Load current is

    1. A 72 A
    2. B 0.5 A
    3. C 2 A
    4. D 18 A
    💡 Explanation:

    I = V/R = 2 A.

  48. Q48 easy

    A 18 V source drives 6 ohm load. Load current is

    1. A 108 A
    2. B 0.3333333333333333 A
    3. C 3 A
    4. D 24 A
    💡 Explanation:

    I = V/R = 3 A.

  49. Q49 easy

    A 9 V source drives 3 ohm load. Load current is

    1. A 27 A
    2. B 3 A
    3. C 0.3333333333333333 A
    4. D 12 A
    💡 Explanation:

    I = V/R = 3 A.

  50. Q50 easy

    A 16 V source drives 4 ohm load. Load current is

    1. A 64 A
    2. B 0.25 A
    3. C 4 A
    4. D 20 A
    💡 Explanation:

    I = V/R = 4 A.

  51. Q51 medium

    4 ohm, 6 ohm, 10 ohm in series across 20 V gives current

    1. A 2 A
    2. B 0.5 A
    3. C 20 A
    4. D 1 A
    💡 Explanation:

    R = 20 ohm; I = 20/20 = 1 A.

  52. Q52 medium

    5 ohm, 5 ohm, 10 ohm in series across 20 V gives current

    1. A 1 A
    2. B 2 A
    3. C 0.5 A
    4. D 20 A
    💡 Explanation:

    R = 20 ohm; I = 20/20 = 1 A.

  53. Q53 medium

    1 ohm, 2 ohm, 7 ohm in series across 10 V gives current

    1. A 2 A
    2. B 1 A
    3. C 0.5 A
    4. D 10 A
    💡 Explanation:

    R = 10 ohm; I = 10/10 = 1 A.

  54. Q54 Past Paper · PPSC/FPSC/CSS easy

    A 20 ohm resistor carries 3 A. The voltage across it is

    1. A 6.666666666666667 V
    2. B 60 V
    3. C 600 V
    4. D 0.15 V
    💡 Explanation:

    V = IR = 20 × 3 = 60 V.

  55. Q55 medium

    3 ohm, 3 ohm, 4 ohm in series across 10 V gives current

    1. A 1 A
    2. B 2 A
    3. C 0.5 A
    4. D 10 A
    💡 Explanation:

    R = 10 ohm; I = 10/10 = 1 A.

  56. Q56 medium

    Resistors 12, 6, 4 ohm in parallel give

    1. A 22 ohm
    2. B 2 ohm
    3. C 12 ohm
    4. D 36 ohm
    💡 Explanation:

    1/Req = 1/12+1/6+1/4; Req = 2 ohm.

  57. Q57 medium

    Resistors 10, 15, 30 ohm in parallel give

    1. A 5 ohm
    2. B 55 ohm
    3. C 10 ohm
    4. D 30 ohm
    💡 Explanation:

    1/Req = 1/10+1/15+1/30; Req = 5 ohm.

  58. Q58 medium

    Resistors 8, 8, 8 ohm in parallel give

    1. A 24 ohm
    2. B 8 ohm
    3. C 8/3 ohm
    4. D 4 ohm
    💡 Explanation:

    1/Req = 1/8+1/8+1/8; Req = 8/3 ohm.

  59. Q59 medium

    Resistors 20, 10, 20 ohm in parallel give

    1. A 5 ohm
    2. B 50 ohm
    3. C 20 ohm
    4. D 60 ohm
    💡 Explanation:

    1/Req = 1/20+1/10+1/20; Req = 5 ohm.

  60. Q60 medium

    Resistors 6, 3, 2 ohm in parallel give

    1. A 11 ohm
    2. B 1 ohm
    3. C 6 ohm
    4. D 18 ohm
    💡 Explanation:

    1/Req = 1/6+1/3+1/2; Req = 1 ohm.

  61. Q61 Past Paper · PPSC/FPSC/CSS easy

    A 12 ohm resistor carries 5 A. The voltage across it is

    1. A 2.4 V
    2. B 60 V
    3. C 600 V
    4. D 0.4166666666666667 V
    💡 Explanation:

    V = IR = 12 × 5 = 60 V.

  62. Q62 Past Paper · PPSC/FPSC/CSS easy

    Two resistors 10 ohm and 40 ohm in parallel have equivalent resistance of

    1. A 50 ohm
    2. B 400 ohm
    3. C 8 ohm
    4. D 0.25 ohm
    💡 Explanation:

    Parallel: 1/R = 1/10+1/40; R = 8 ohm.

  63. Q63 Past Paper · PPSC/FPSC/CSS easy

    Two resistors 20 ohm and 5 ohm in parallel have equivalent resistance of

    1. A 25 ohm
    2. B 100 ohm
    3. C 1.25 ohm
    4. D 4 ohm
    💡 Explanation:

    Parallel: 1/R = 1/20+1/5; R = 4 ohm.

  64. Q64 Past Paper · PPSC/FPSC/CSS easy

    Two resistors 6 ohm and 3 ohm in parallel have equivalent resistance of

    1. A 2 ohm
    2. B 9 ohm
    3. C 18 ohm
    4. D 1 ohm
    💡 Explanation:

    Parallel: 1/R = 1/6+1/3; R = 2 ohm.

  65. Q65 Past Paper · PPSC/FPSC/CSS easy

    Two resistors 12 ohm and 4 ohm in parallel have equivalent resistance of

    1. A 16 ohm
    2. B 3 ohm
    3. C 48 ohm
    4. D 0.75 ohm
    💡 Explanation:

    Parallel: 1/R = 1/12+1/4; R = 3 ohm.

  66. Q66 Past Paper · PPSC/FPSC/CSS easy

    Resistors 4 ohm, 8 ohm connected in series have equivalent resistance of

    1. A 6 ohm
    2. B 4 ohm
    3. C 32 ohm
    4. D 12 ohm
    💡 Explanation:

    Series: R = 4+8 = 12 ohm.

  67. Q67 Past Paper · PPSC/FPSC/CSS easy

    A 15 ohm resistor carries 4 A. The voltage across it is

    1. A 3.75 V
    2. B 600 V
    3. C 60 V
    4. D 0.26666666666666666 V
    💡 Explanation:

    V = IR = 15 × 4 = 60 V.

  68. Q68 Past Paper · PPSC/FPSC/CSS easy

    A 50 ohm resistor carries 0.5 A. The voltage across it is

    1. A 100 V
    2. B 25 V
    3. C 250 V
    4. D 0.01 V
    💡 Explanation:

    V = IR = 50 × 0.5 = 25 V.

  69. Q69 Past Paper · PPSC/FPSC/CSS easy

    A 100 ohm resistor carries 0.2 A. The voltage across it is

    1. A 20 V
    2. B 500 V
    3. C 200 V
    4. D 0.002 V
    💡 Explanation:

    V = IR = 100 × 0.2 = 20 V.

  70. Q70 Past Paper · PPSC/FPSC/CSS easy

    A 25 ohm resistor carries 2 A. The voltage across it is

    1. A 50 V
    2. B 12.5 V
    3. C 500 V
    4. D 0.08 V
    💡 Explanation:

    V = IR = 25 × 2 = 50 V.

  71. Q71 Past Paper · PPSC/FPSC/CSS easy

    Two resistors 8 ohm and 8 ohm in parallel have equivalent resistance of

    1. A 16 ohm
    2. B 64 ohm
    3. C 4 ohm
    4. D 1 ohm
    💡 Explanation:

    Parallel: 1/R = 1/8+1/8; R = 4 ohm.

  72. Q72 Past Paper · PPSC/FPSC/CSS easy

    Resistors 5 ohm, 7 ohm, 3 ohm connected in series have equivalent resistance of

    1. A 15 ohm
    2. B 7.5 ohm
    3. C 5 ohm
    4. D 105 ohm
    💡 Explanation:

    Series: R = 5+7+3 = 15 ohm.

  73. Q73 Past Paper · PPSC/FPSC/CSS easy

    Resistors 2 ohm, 2 ohm, 2 ohm connected in series have equivalent resistance of

    1. A 6 ohm
    2. B 3 ohm
    3. C 2 ohm
    4. D 8 ohm
    💡 Explanation:

    Series: R = 2+2+2 = 6 ohm.

  74. Q74 easy

    Balanced Wheatstone bridge galvanometer shows

    1. A zero deflection
    2. B maximum deflection always
    3. C unstable oscillation always
    4. D short circuit current
    💡 Explanation:

    Zero current in galvanometer at balance.

  75. Q75 hard

    Wheatstone bridge P=100, Q=200, R=150 ohm; unknown S at balance is

    1. A 75 ohm
    2. B 300 ohm
    3. C 50 ohm
    4. D 450 ohm
    💡 Explanation:

    100/200 = 150/S → S = 300 ohm.

  76. Q76 Past Paper · PPSC/FPSC/CSS easy

    A 10 ohm resistor carries 2 A. The voltage across it is

    1. A 5 V
    2. B 200 V
    3. C 20 V
    4. D 0.2 V
    💡 Explanation:

    V = IR = 10 × 2 = 20 V.

  77. Q77 Past Paper · PPSC/FPSC/CSS easy

    A 5 ohm resistor carries 4 A. The voltage across it is

    1. A 1.25 V
    2. B 200 V
    3. C 0.8 V
    4. D 20 V
    💡 Explanation:

    V = IR = 5 × 4 = 20 V.

  78. Q78 Past Paper · PPSC/FPSC/CSS easy

    Kirchhoff Current Law at a node states that

    1. A sum of voltages is zero
    2. B sum of currents entering equals sum leaving
    3. C current is same in all branches
    4. D power is zero always
    💡 Explanation:

    KCL follows from conservation of charge.

  79. Q79 Past Paper · PPSC/FPSC/CSS easy

    Kirchhoff Voltage Law around a closed loop states that

    1. A sum of currents is zero
    2. B algebraic sum of voltage drops is zero
    3. C sum of resistances is zero
    4. D current equals voltage
    💡 Explanation:

    KVL follows from conservation of energy.

  80. Q80 Past Paper · PPSC/FPSC/CSS easy

    Power dissipated in a resistor carrying current I is

    1. A I divided by R
    2. B R divided by I only
    3. C I times R only
    4. D I squared times R
    💡 Explanation:

    P = I²R = VI = V²/R for a resistor.

  81. Q81 Past Paper · PPSC/FPSC/CSS easy

    Conductance G of resistance R equals

    1. A R
    2. B R squared
    3. C 1/R
    4. D square root of R
    💡 Explanation:

    G = 1/R in siemens.

  82. Q82 Past Paper · PPSC/FPSC/CSS easy

    In a series circuit the current through each element is

    1. A inversely proportional to R always
    2. B the same
    3. C zero in largest R
    4. D divided equally by voltage
    💡 Explanation:

    Single path: same current everywhere.

  83. Q83 Past Paper · PPSC/FPSC/CSS easy

    In a parallel circuit the voltage across each branch is

    1. A proportional to branch resistance
    2. B always zero
    3. C the same
    4. D sum of branch voltages
    💡 Explanation:

    Parallel branches share the same potential.

  84. Q84 Past Paper · PPSC/FPSC/CSS medium

    A 100 W, 250 V lamp has hot resistance approximately

    1. A 2.5 ohm
    2. B 25 ohm
    3. C 2500 ohm
    4. D 625 ohm
    💡 Explanation:

    R = V²/P = 62500/100 = 625 ohm.

  85. Q85 Past Paper · PPSC/FPSC/CSS medium

    A 220 V, 1000 W heater resistance is approximately

    1. A 48.4 ohm
    2. B 220 ohm
    3. C 22 ohm
    4. D 484 ohm
    💡 Explanation:

    R = V²/P = 48400/1000 = 48.4 ohm.

  86. Q86 easy

    Energy in a pure resistor is

    1. A stored in magnetic field
    2. B dissipated as heat
    3. C stored as charge permanently
    4. D converted to inductance
    💡 Explanation:

    Resistors dissipate; they do not store energy.

  87. Q87 easy

    A practical ammeter should have

    1. A very high internal resistance
    2. B infinite resistance
    3. C same R as voltmeter
    4. D very low internal resistance
    💡 Explanation:

    Low R minimizes loading error.

  88. Q88 easy

    Thevenin equivalent of a linear network is

    1. A voltage source Vth in series with Rth
    2. B current source only
    3. C single resistor only
    4. D capacitor in series
    💡 Explanation:

    Thevenin: Vth + series Rth.

  89. Q89 easy

    Norton equivalent of a linear network is

    1. A voltage source in parallel with R
    2. B short circuit only
    3. C current source In in parallel with Rn
    4. D open circuit only
    💡 Explanation:

    Norton: In || Rn.

  90. Q90 medium

    Thevenin voltage Vth is measured as

    1. A open-circuit terminal voltage
    2. B short-circuit current
    3. C load current at max power
    4. D internal drop only
    💡 Explanation:

    Vth = Voc at terminals.

  91. Q91 medium

    Thevenin resistance Rth is found by

    1. A adding all resistors always
    2. B measuring loaded voltage only
    3. C deactivating sources and looking into terminals
    4. D multiplying branch currents
    💡 Explanation:

    Zero sources; compute R at terminals.

  92. Q92 medium

    Norton current In equals

    1. A short-circuit terminal current
    2. B open-circuit voltage
    3. C Thevenin resistance
    4. D load current always
    💡 Explanation:

    In = Isc at terminals.

  93. Q93 medium

    For maximum power transfer to load, R_L should equal

    1. A Rth
    2. B zero
    3. C twice Rth always
    4. D half Rth always
    💡 Explanation:

    Max power when R_L = Rth.

  94. Q94 hard

    Maximum power when Vth=20 V and Rth=5 ohm with matched load is

    1. A 20 W
    2. B 100 W
    3. C 40 W
    4. D 10 W
    💡 Explanation:

    Pmax = V²/(4R) = 400/20 = 20 W.

  95. Q95 hard

    At maximum power transfer the efficiency is

    1. A 100 percent
    2. B 25 percent
    3. C 50 percent
    4. D 75 percent
    💡 Explanation:

    Half power in Rth, half in R_L.

  96. Q96 medium

    Superposition applies to

    1. A saturated magnetic cores only
    2. B nonlinear diodes only
    3. C linear bilateral networks
    4. D single-source circuits only
    💡 Explanation:

    Response = sum of individual source responses.

  97. Q97 medium

    When using superposition, other voltage sources are replaced by

    1. A open circuits
    2. B their load resistances
    3. C short circuits
    4. D infinite inductors
    💡 Explanation:

    Ideal voltage sources → shorts.

  98. Q98 medium

    When using superposition, other current sources are replaced by

    1. A short circuits
    2. B open circuits
    3. C Thevenin resistances
    4. D matched loads
    💡 Explanation:

    Ideal current sources → opens.

  99. Q99 medium

    Superposition cannot find directly

    1. A node voltage from one source
    2. B branch current from one source
    3. C total power in a resistor with multiple sources
    4. D Thevenin voltage
    💡 Explanation:

    Power is nonlinear in current.

  100. Q100 medium

    If Vth=12 V and Rth=4 ohm, Norton current is

    1. A 48 A
    2. B 0.33 A
    3. C 3 A
    4. D 8 A
    💡 Explanation:

    In = Vth/Rth = 3 A.

  101. Q101 medium

    Source transformation: V in series with R becomes current source

    1. A V times R in series
    2. B V/R in parallel with R
    3. C R/V in parallel
    4. D V in parallel with R only
    💡 Explanation:

    I = V/R with same R.

  102. Q102 hard

    Reciprocity theorem applies to

    1. A nonlinear networks only
    2. B unilateral devices only
    3. C magnetic saturation regions
    4. D linear bilateral networks
    💡 Explanation:

    Interchange excitation and response in linear bilateral nets.

  103. Q103 medium

    Mesh analysis uses

    1. A KCL at capacitors only
    2. B flux linkage only
    3. C only Ohm law at one node
    4. D KVL around independent loops
    💡 Explanation:

    Mesh currents + KVL per loop.

  104. Q104 medium

    Nodal analysis uses

    1. A KVL around every resistor
    2. B only Thevenin equivalents
    3. C KCL at nodes with voltage unknowns
    4. D magnetic flux balance
    💡 Explanation:

    Node voltages + KCL.

  105. Q105 medium

    Independent nodal equations for n nodes number

    1. A n
    2. B n plus 1
    3. C n squared
    4. D n minus 1
    💡 Explanation:

    One reference node at 0 V.

  106. Q106 hard

    Independent mesh equations for b branches and n nodes in planar net

    1. A n minus 1
    2. B b minus n plus 1
    3. C b plus n
    4. D b times n
    💡 Explanation:

    Independent loops = b - n + 1.

  107. Q107 medium

    A Wheatstone bridge is balanced when

    1. A all resistances equal only
    2. B galvanometer reads maximum
    3. C supply is zero
    4. D ratio of adjacent arms on one side equals the other
    💡 Explanation:

    Balance: P/Q = R/S.

  108. Q108 Past Paper · PPSC/FPSC/CSS easy

    A 4 ohm resistor carries 7 A. The voltage across it is

    1. A 0.5714285714285714 V
    2. B 28 V
    3. C 280 V
    4. D 1.75 V
    💡 Explanation:

    V = IR = 4 × 7 = 28 V.

  109. Q109 Past Paper · PPSC/FPSC/CSS easy

    Resistors 10 ohm, 15 ohm connected in series have equivalent resistance of

    1. A 25 ohm
    2. B 12.5 ohm
    3. C 10 ohm
    4. D 150 ohm
    💡 Explanation:

    Series: R = 10+15 = 25 ohm.

  110. Q110 Past Paper · PPSC/FPSC/CSS easy

    Resistors 6 ohm, 3 ohm connected in series have equivalent resistance of

    1. A 4.5 ohm
    2. B 9 ohm
    3. C 6 ohm
    4. D 18 ohm
    💡 Explanation:

    Series: R = 6+3 = 9 ohm.

  111. Q111 Past Paper · PPSC/FPSC/CSS easy

    A 8 ohm resistor carries 2.5 A. The voltage across it is

    1. A 3.2 V
    2. B 200 V
    3. C 0.3125 V
    4. D 20 V
    💡 Explanation:

    V = IR = 8 × 2.5 = 20 V.