EE 210 Exam 1: Circuit Analysis with
correct Answers and rationale
updated 2026 graded A+
SECTION 1: BASIC CONCEPTS AND UNITS (Questions 1-15)
1. What is the SI unit of electric charge?
A) Ampere
B) Coulomb ✓
C) Volt
D) Ohm
Rationale: The coulomb (C) is the SI unit of electric charge, where 1 C = 6.242 × 10¹⁸ electrons.
2. One ampere is equivalent to:
A) 1 Joule/Coulomb
B) 1 Coulomb/second ✓
C) 1 Volt/Ohm × second
D) 1 Watt/Volt × second
Rationale: Current is defined as the rate of flow of charge: I = dQ/dt, so 1 A = 1 C/s.
3. The voltage across an element is defined as:
A) Charge per unit time
B) Energy per unit charge ✓
C) Power per unit current
D) Resistance per unit current
Rationale: Voltage (V) = Energy (J) / Charge (C); 1 V = 1 J/C.
,4. Power is measured in:
A) Joules
B) Coulombs
C) Watts ✓
D) Volts
Rationale: Power is the rate of energy transfer; 1 watt = 1 joule/second.
5. Which of the following is a passive element?
A) Battery
B) Current source
C) Resistor ✓
D) Op-amp
Rationale: Passive elements (R, L, C) cannot deliver more energy than they absorb; only resistors
from this list are passive.
6. The prefix "milli" represents:
A) 10⁻⁶
B) 10⁻³ ✓
C) 10⁻⁹
D) 10⁻¹²
Rationale: "Milli" is the SI prefix for one-thousandth (10⁻³).
7. Convert 5 kΩ to ohms:
A) 500 Ω
B) 5,000 Ω ✓
C) 50,000 Ω
D) 0.005 Ω
,Rationale: kilo = 10³, so 5 kΩ × 1000 = 5,000 Ω.
8. The reference direction for current is:
A) Direction of electron flow
B) Direction of positive charge flow ✓
C) Always left to right
D) Always top to bottom
Rationale: Conventional current flows in the direction of positive charge, opposite to electron flow.
9. Which element stores energy in an electric field?
A) Resistor
B) Inductor
C) Capacitor ✓
D) Diode
Rationale: Capacitors store energy in the electric field between their plates: W = ½CV².
10. Which element stores energy in a magnetic field?
A) Capacitor
B) Inductor ✓
C) Resistor
D) Transformer core
Rationale: Inductors store energy in a magnetic field: W = ½LI².
11. An ideal voltage source has:
A) Infinite internal resistance
B) Zero internal resistance ✓
C) Variable resistance
, D) Equal to load resistance
Rationale: An ideal voltage source maintains constant voltage regardless of load, requiring zero
internal resistance.
12. An ideal current source has:
A) Zero internal resistance
B) Infinite internal resistance ✓
C) Finite resistance
D) Negative resistance
Rationale: An ideal current source delivers constant current regardless of voltage across it, requiring
infinite internal resistance.
13. If 20 C of charge pass a point in 4 seconds, the current is:
A) 4 A
B) 5 A ✓
C) 80 A
D) 0.2 A
Rationale: I = Q/t = 20 C / 4 s = 5 A.
14. The energy consumed when 10 C moves through a potential difference of 12 V is:
A) 22 J
B) 120 J ✓
C) 1.2 J
D) 12 J
Rationale: W = QV = 10 × 12 = 120 J.
15. A device that converts electrical energy to another form is called:
correct Answers and rationale
updated 2026 graded A+
SECTION 1: BASIC CONCEPTS AND UNITS (Questions 1-15)
1. What is the SI unit of electric charge?
A) Ampere
B) Coulomb ✓
C) Volt
D) Ohm
Rationale: The coulomb (C) is the SI unit of electric charge, where 1 C = 6.242 × 10¹⁸ electrons.
2. One ampere is equivalent to:
A) 1 Joule/Coulomb
B) 1 Coulomb/second ✓
C) 1 Volt/Ohm × second
D) 1 Watt/Volt × second
Rationale: Current is defined as the rate of flow of charge: I = dQ/dt, so 1 A = 1 C/s.
3. The voltage across an element is defined as:
A) Charge per unit time
B) Energy per unit charge ✓
C) Power per unit current
D) Resistance per unit current
Rationale: Voltage (V) = Energy (J) / Charge (C); 1 V = 1 J/C.
,4. Power is measured in:
A) Joules
B) Coulombs
C) Watts ✓
D) Volts
Rationale: Power is the rate of energy transfer; 1 watt = 1 joule/second.
5. Which of the following is a passive element?
A) Battery
B) Current source
C) Resistor ✓
D) Op-amp
Rationale: Passive elements (R, L, C) cannot deliver more energy than they absorb; only resistors
from this list are passive.
6. The prefix "milli" represents:
A) 10⁻⁶
B) 10⁻³ ✓
C) 10⁻⁹
D) 10⁻¹²
Rationale: "Milli" is the SI prefix for one-thousandth (10⁻³).
7. Convert 5 kΩ to ohms:
A) 500 Ω
B) 5,000 Ω ✓
C) 50,000 Ω
D) 0.005 Ω
,Rationale: kilo = 10³, so 5 kΩ × 1000 = 5,000 Ω.
8. The reference direction for current is:
A) Direction of electron flow
B) Direction of positive charge flow ✓
C) Always left to right
D) Always top to bottom
Rationale: Conventional current flows in the direction of positive charge, opposite to electron flow.
9. Which element stores energy in an electric field?
A) Resistor
B) Inductor
C) Capacitor ✓
D) Diode
Rationale: Capacitors store energy in the electric field between their plates: W = ½CV².
10. Which element stores energy in a magnetic field?
A) Capacitor
B) Inductor ✓
C) Resistor
D) Transformer core
Rationale: Inductors store energy in a magnetic field: W = ½LI².
11. An ideal voltage source has:
A) Infinite internal resistance
B) Zero internal resistance ✓
C) Variable resistance
, D) Equal to load resistance
Rationale: An ideal voltage source maintains constant voltage regardless of load, requiring zero
internal resistance.
12. An ideal current source has:
A) Zero internal resistance
B) Infinite internal resistance ✓
C) Finite resistance
D) Negative resistance
Rationale: An ideal current source delivers constant current regardless of voltage across it, requiring
infinite internal resistance.
13. If 20 C of charge pass a point in 4 seconds, the current is:
A) 4 A
B) 5 A ✓
C) 80 A
D) 0.2 A
Rationale: I = Q/t = 20 C / 4 s = 5 A.
14. The energy consumed when 10 C moves through a potential difference of 12 V is:
A) 22 J
B) 120 J ✓
C) 1.2 J
D) 12 J
Rationale: W = QV = 10 × 12 = 120 J.
15. A device that converts electrical energy to another form is called:
