Renñier A.
Salvador
BSECE 4-5
50 Problem Set
DC Electrical Circuits
1. In a series RLC circuit, if the resistance is 10 Ω, the inductance is 0.2 H, and the capacitance is
100 µF, what is the resonant frequency?
A) 159.15 Hz
B) 1591.5 Hz
C) 15.91 Hz
D) 1590 Hz
2. For a series RLC circuit with R = 5 Ω, L = 0.1 H, and C = 10 µF, find the total impedance at
resonance.
A) 0 Ω
B) 5 Ω
C) 10 Ω
D) 100 Ω
3. In an RLC series circuit, if the frequency is increased above the resonance frequency, the
impedance will:
A) Decrease
B) Increase
C) Stay constant
D) Become zero
4. Given an RLC circuit with R = 2 Ω, L = 0.4 H, and C = 50 µF, if the applied voltage is 10 V at
resonance, calculate the current.
A) 2 A
B) 5 A
C) 10 A
D) 4 A
5. In a series RLC circuit, if the total impedance is 15 Ω, the resistance is 10 Ω, and the inductive
reactance is 12 Ω, what is the capacitive reactance?
A) 7 Ω
B) 5 Ω
C) 15 Ω
D) 20 Ω
6. For a parallel circuit with resistors R₁ = 10 Ω, R₂ = 20 Ω, and R₃ = 30 Ω, what is the total
resistance?
A) 5.45 Ω
B) 12 Ω
C) 60 Ω
D) 20 Ω
7. If three resistors R₁ = 4 Ω, R₂ = 6 Ω, and R₃ = 12 Ω are connected in series, what is the total
resistance?
A) 22 Ω
B) 18 Ω
C) 24 Ω
D) 14 Ω
8. In a parallel circuit, if the voltage across each resistor is 10 V and the resistances are 5 Ω, 10 Ω,
and 20 Ω, calculate the total current.
A) 2 A
B) 3 A
o C) 1.5 A
D) 5 A
9. In a series circuit with R₁ = 5 Ω, R₂ = 10 Ω, and an applied voltage of 30 V, what is the total
current?
A) 2 A
B) 3 A
C) 5 A
D) 6 A
10. For a parallel network with resistors R₁ = 6 Ω, R₂ = 3 Ω, and R₃ = 2 Ω, what is the equivalent
resistance?
A) 1 Ω
B) 2 Ω
C) 4 Ω
D) 0.8 Ω
11. Using Kirchhoff's Voltage Law (KVL), find the unknown voltage V in a circuit with resistors R₁ =
10 Ω, R₂ = 5 Ω, and a 20 V supply, given the current through R₁ is 2 A.
A) 5 V
B) 10 V
C) 15 V
D) 20 V
12. In a circuit with two resistors R₁ = 8 Ω and R₂ = 4 Ω connected in parallel, and a current of 3 A
flowing, calculate the total current.
A) 2 A
B) 3 A
C) 4 A
D) 5 A
13. In a series circuit with resistors R₁ = 4 Ω, R₂ = 8 Ω, and R₃ = 12 Ω, if the total current is 2 A,
calculate the voltage drop across R₃.
A) 24 V
B) 12 V
C) 8 V
D) 4 V
14. Using Thevenin's Theorem, calculate the Thevenin resistance for a network of resistors R₁ = 5
Ω and R₂ = 10 Ω connected in series.
A) 5 Ω
B) 10 Ω
C) 15 Ω
D) 0 Ω
15. In a mesh analysis, if the mesh currents I₁ = 3 A, I₂ = 2 A, and the resistances are R₁ = 10 Ω and
R₂ = 20 Ω, calculate the power dissipated in R₁.
A) 90 W
B) 60 W
C) 45 W
D) 30 W
16. In an RL circuit, if the inductance is 2 H and the resistance is 4 Ω, calculate the time constant.
A) 0.5 s
B) 1 s
C) 2 s
D) 8 s
17. For an RL circuit with L = 10 H, R = 5 Ω, and a DC source of 20 V, calculate the initial current.
A) 0 A
B) 4 A
C) 2 A
D) 10 A
18. In an RL circuit, if the current is increasing at a rate of 2 A/s, the inductance is 4 H, and the
resistance is 8 Ω, calculate the applied voltage.
A) 16 V
B) 8 V
C) 10 V
D) 4 V
19. In an RC circuit, if the resistance is 3 Ω and the capacitance is 2 µF, calculate the time constant.
A) 6 µs
B) 0.006 s
C) 6 s
D) 0.6 µs
20. For an RC circuit, if the initial voltage across the capacitor is 15 V and the resistance is 10 Ω,
calculate the voltage across the capacitor after 2 time constants.
A) 5 V
B) 10 V
C) 12 V
D) 15 V
21. What is the total resistance in a circuit with resistors R₁ = 8 Ω, R₂ = 8 Ω, and R₃ = 8 Ω in
parallel?
A) 4 Ω
B) 2.67 Ω
C) 6 Ω
D) 16 Ω
22. In a parallel circuit with resistors R₁ = 5 Ω, R₂ = 10 Ω, and R₃ = 15 Ω, calculate the total current
if the applied voltage is 30 V.
A) 3 A
B) 4 A
C) 5 A
D) 6 A
23. In a series circuit with a voltage supply of 24 V, if the resistors are R₁ = 4 Ω, R₂ = 6 Ω, and R₃ = 8
Ω, what is the total current?
A) 2 A
B) 3 A
C) 4 A
D) 6 A
24. For a parallel network, if the resistors are R₁ = 20 Ω, R₂ = 40 Ω, and R₃ = 60 Ω, what is the total
current for an applied voltage of 12 V?
A) 0.5 A
B) 1 A
C) 2 A
D) 4 A
25. What is the total resistance in a circuit with resistors R₁ = 5 Ω, R₂ = 5 Ω in series and R₃ = 5 Ω in
parallel to the combination?
A) 3.33 Ω
B) 5 Ω
C) 7.5 Ω
D) 10 Ω
26. Using Norton's Theorem, what is the equivalent current source for a circuit with R₁ = 4 Ω, R₂ =
6 Ω, and a supply of 20 V?
A) 2 A
B) 5 A
C) 4 A
D) 1 A
27. Using Kirchhoff’s Current Law (KCL), calculate the current I₃ if currents I₁ = 3 A and I₂ = 2 A
enter a junction.
A) 1 A
B) 3 A
C) 5 A
D) 0 A
28. In a series circuit with a 24V battery, a 10Ω, a 20Ω, and a 30Ω resistor are connected. What is the
total current?
a) 0.5A
b) 1A
c) 1.2A
d) 2A
Answer:
b) 1A
29. A parallel circuit consists of a 6Ω and a 12Ω resistor. What is the total resistance?
a) 4Ω
b) 3Ω
c) 2Ω
d) 1Ω
Answer:
b) 4Ω
30. In a series circuit with a 12V battery, a 3Ω and a 4Ω resistor are connected. What is the current?
a) 2A
b) 3A
c) 1.2A
d) 0.5A
Answer:
a) 2A
31. What is the time constant of a circuit with a 100Ω resistor and a 10μF capacitor?
a) 1s
b) 0.001s
c) 0.01s
d) 0.1s
Answer:
b) 0.001s
32. A 12V battery is connected to a 6Ω resistor and a 3H inductor. What is the current after a long time?
a) 0A
b) 2A
c) 3A
d) 5A
Answer:
d) 5A
33. A 50Ω and a 20Ω resistor are connected in parallel across a 12V battery. What is the current through
the 50Ω resistor?
a) 0.24A
b) 0.48A
c) 0.6A
d) 1A
Answer:
a) 0.24A
34. What is the resonant frequency of an RLC circuit with a 2Ω resistor, 2H inductor, and 0.5μF
capacitor?
a) 159.15Hz
b) 1591.5Hz
c) 1kHz
d) 100Hz
Answer:
a) 159.15Hz
35. A circuit consists of a 10V battery and a 4Ω resistor. What is the current?
a) 2A
b) 1A
c) 0.5A
d) 4A
Answer:
b) 2A
36. A 10V battery is connected to a series combination of a 2Ω resistor and a 4Ω resistor. What is the
total resistance?
a) 6Ω
b) 8Ω
c) 4Ω
d) 2Ω
Answer:
a) 6Ω
37. A 10V battery is connected to an RL circuit with a 10Ω resistor and a 2H inductor. What is the time
constant?
a) 0.2s
b) 2s
c) 0.5s
d) 5s
Answer:
a) 0.2s
38. A 12V battery is connected to a 4Ω resistor. What is the power dissipated?
a) 3W
b) 6W
c) 12W
d) 24W
Answer:
b) 6W
39. A 10Ω resistor is connected in series with a 12V battery. What is the current in the circuit?
a) 1A
b) 2A
c) 0.5A
d) 0.2A
Answer:
a) 1A
40. A capacitor of 100μF is charged to 10V. What is the charge on the capacitor?
a) 1mC
b) 10mC
c) 100mC
d) 0.1mC
Answer:
b) 10mC
41. In a series circuit, a 6Ω resistor, a 4Ω resistor, and a 2Ω resistor are connected to a 12V battery. What
is the total current?
a) 1A
b) 2A
c) 3A
d) 0.5A
Answer:
b) 2A
42. What is the voltage across a 6Ω resistor if the current is 3A?
a) 18V
b) 12V
c) 6V
d) 2V
Answer:
a) 18V
43. A 12V battery is connected to two resistors in parallel: 12Ω and 24Ω. What is the total current?
a) 0.5A
b) 1A
c) 2A
d) 3A
Answer:
b) 1A
44. An RL circuit has a 10Ω resistor and a 2H inductor. What is the time constant?
a) 0.5s
b) 2s
c) 0.2s
d) 0.1s
Answer:
a) 0.5s
45. In a series RLC circuit, the resistance is 4Ω, the inductance is 2H, and the capacitance is 100μF. What
is the impedance at 50Hz?
a) 10Ω
b) 20Ω
c) 25Ω
d) 30Ω
Answer:
c) 25Ω
46. What is the current in a circuit with a 24V battery, a 12Ω resistor, and a 6Ω resistor connected in
parallel?
a) 1A
b) 2A
c) 3A
d) 4A
Answer:
b) 2A
47. In a series circuit with a 10V battery and a 5Ω resistor, what is the power dissipated?
a) 5W
b) 10W
c) 15W
d) 20W
Answer:
a) 5W
48. A 10V battery is connected to an RL circuit with a 5Ω resistor and a 3H inductor. What is the current
after a long time?
a) 0A
b) 2A
c) 1A
d) 3A
Answer:
b) 2A
49. A circuit with a 12V battery is connected to a 3Ω resistor and a 6Ω resistor in series. What is the total
current?
a) 2A
b) 1A
c) 3A
d) 4A
Answer:
a) 2A
50. In a parallel circuit, the total current is 5A, and there are two branches: one with a 10Ω resistor and
the other with a 20Ω resistor. What is the voltage across the 10Ω resistor?
a) 10V
b) 20V
c) 30V
d) 50V
Answer:
a) 10V
