Electric Circuits: Master the Fundamentals with Interactive Quizzes

Question 1

In an electric circuit, which equation represents Ohm's law, relating voltage (V), current (I), and resistance (R)?

Accepted Answer

V = IR

Answer

I = VR

Answer

R = IV

Answer

V = I/R

Question 2

To determine the unknown current in a circuit, how should Kirchhoff's Current and Voltage Laws be applied?

Accepted Answer

Apply Kirchhoff's Current Law at junctions and Kirchhoff's Voltage Law around loops.

Answer

Apply Kirchhoff's Current Law at junctions only.

Answer

Apply Kirchhoff's Voltage Law around loops only.

Answer

Kirchhoff's laws cannot be used to determine the unknown current in a circuit.

Question 3

In a complete electric circuit, the algebraic sum of the potential differences around the circuit is:

Accepted Answer

Zero

Answer

Always positive

Answer

Always negative

Answer

Depends on the direction of the current

Question 4

Which of the following is the SI unit of resistance?

Accepted Answer

Ohm

Answer

Ampere

Answer

Volt

Answer

Coulomb

Question 5

A capacitor is a device that stores:

Accepted Answer

Electric charge

Answer

Electric current

Answer

Magnetic energy

Answer

Kinetic energy

Question 6

The time constant of an RL circuit is defined as:

Accepted Answer

The time it takes for the current to decay to half its initial value

Answer

The time it takes for the current to reach its maximum value

Answer

The time it takes for the voltage to reach its maximum value

Answer

The time it takes for the voltage to decay to half its initial value

Question 7

An inductor is a device that stores:

Accepted Answer

Magnetic energy

Answer

Electric charge

Answer

Electric current

Answer

Kinetic energy

Question 8

Which of the following is a characteristic of AC circuits?

Accepted Answer

The current and voltage are constantly changing direction

Answer

The current and voltage are always in phase

Answer

The current and voltage are always out of phase

Answer

The current and voltage are always constant

Question 9

A transformer is a device that transfers:

Accepted Answer

Electric power from one circuit to another

Answer

Electric charge from one circuit to another

Answer

Magnetic energy from one circuit to another

Answer

Kinetic energy from one circuit to another

Question 10

Which of the following is the SI unit of electric current?

Accepted Answer

Ampere (A)

Answer

Volt (V)

Answer

Ohm (Ω)

Answer

Coulomb (C)

Question 11

Ohm's law states that the current (I) flowing through a conductor is directly proportional to the:

Accepted Answer

Voltage (V) across the conductor

Answer

Resistance (R) of the conductor

Answer

Frequency of the AC current

Question 12

A device that converts electrical energy into mechanical energy is called a:

Accepted Answer

Motor

Answer

Generator

Answer

Transformer

Answer

Battery

Question 13

Kirchhoff's junction rule states that the total current flowing into a junction is equal to the total current flowing out of the junction.

Accepted Answer

True

Answer

False

Question 14

Capacitors store electrical energy in the form of:

Accepted Answer

Electric field

Answer

Magnetic field

Answer

Gravitational field

Answer

Thermal energy

Question 15

Inductors store electrical energy in the form of:

Accepted Answer

Magnetic field

Answer

Electric field

Answer

Chemical energy

Answer

Light energy

Question 16

Which of the following circuits has a power factor of 1?

Accepted Answer

Purely resistive

Answer

Purely inductive

Answer

Purely capacitive

Answer

RLC circuit with equal R and L/C

Question 17

In an AC circuit, the impedance is the vector sum of:

Accepted Answer

Resistance and reactance

Answer

Resistance and capacitance

Answer

Inductance and capacitance

Answer

Voltage and current

Question 18

Which of the following is NOT a fundamental component of an electric circuit?

Accepted Answer

Switch

Answer

Battery

Answer

Resistor

Answer

Capacitor

Question 19

Ohm's law states that the current flowing through a conductor is directly proportional to the:

Accepted Answer

Voltage applied to the conductor

Answer

Cross-sectional area of the conductor

Answer

Length of the conductor

Answer

Temperature of the conductor

Question 20

Kirchhoff's current law states that the total current entering a junction must be:

Accepted Answer

Equal to the total current leaving the junction

Answer

Greater than the total current leaving the junction

Answer

Less than the total current leaving the junction

Answer

Zero

Question 21

A circuit with a resistance of 10 ohms is connected to a battery with a voltage of 12 volts. What is the current flowing through the circuit?

Accepted Answer

0.83 A

Answer

1.2 A

Answer

10 A

Answer

12 A

Question 22

Which of the following is a series circuit?

Accepted Answer

A circuit where the components are connected in a single loop

Answer

A circuit where the components are connected in parallel

Answer

A circuit where the components are connected in a combination of series and parallel

Answer

A circuit where the components are not connected

Question 23

What is the purpose of a fuse in an electric circuit?

Accepted Answer

To protect the circuit from excessive current

Answer

To increase the voltage in the circuit

Answer

To decrease the resistance in the circuit

Answer

To store electrical energy

Question 24

Which of the following is a unit of electrical resistance?

Accepted Answer

Ohm

Answer

Ampere

Answer

Volt

Answer

Farad

Question 25

What is the potential difference across a battery?

Accepted Answer

The voltage between the positive and negative terminals

Answer

The current between the positive and negative terminals

Answer

The resistance between the positive and negative terminals

Answer

The power between the positive and negative terminals

Question 26

Which of the following is a characteristic of a superconductor?

Accepted Answer

Zero electrical resistance at very low temperatures

Answer

High electrical resistance

Answer

Low electrical resistance

Answer

Zero magnetic permeability

Question 27

What is the purpose of a capacitor in an electric circuit?

Accepted Answer

To store electrical energy

Answer

To increase the current in the circuit

Answer

To decrease the voltage in the circuit

Answer

To prevent excessive current from flowing through the circuit

Question 28

In a series circuit, the total resistance is:

Accepted Answer

Equal to the sum of the individual resistances

Answer

Less than the sum of the individual resistances

Answer

Greater than the sum of the individual resistances

Answer

Dependent on the voltage applied to the circuit

Question 29

The time constant of a circuit is:

Accepted Answer

The ratio of capacitance to resistance

Answer

The time it takes for the capacitor to reach its maximum charge

Answer

The time it takes for the current to reach its maximum value

Answer

The ratio of inductance to resistance

Question 30

Which of the following is NOT a type of AC (alternating current) circuit?

Accepted Answer

Direct current circuit

Answer

Series circuit

Answer

Parallel circuit

Answer

Resonant circuit

Question 31

The root mean square (RMS) voltage of a sinusoidal waveform is:

Accepted Answer

Less than the peak voltage

Answer

Equal to the peak voltage

Answer

Greater than the peak voltage

Answer

Dependent on the frequency of the waveform

Question 32

Which of the following is a unit of inductance?

Accepted Answer

Henry

Answer

Farad

Answer

Ohm

Answer

Coulomb

Question 33

The impedance of a circuit is:

Accepted Answer

A measure of the total opposition to current flow

Answer

Only applicable to AC circuits

Answer

Equal to the resistance of the circuit

Answer

Independent of the frequency of the applied voltage

Question 34

When resistors are connected in series, what is the relationship between the total resistance and the individual resistances?

Accepted Answer

The total resistance is greater than the largest individual resistance.

Answer

The total resistance is less than the smallest individual resistance.

Answer

The total resistance is equal to the largest individual resistance.

Answer

The total resistance is less than the sum of the individual resistances.

Question 35

An ideal voltmeter has certain characteristics. Which of the following is NOT a property of an ideal voltmeter?

Accepted Answer

Has non-zero internal resistance

Answer

Displays the voltage difference between two points

Answer

Has infinite input impedance

Answer

Measures voltage without affecting the circuit

Question 36

Similar to voltmeters, ideal ammeters also possess specific properties. Which of the following is NOT a characteristic of an ideal ammeter?

Accepted Answer

Has non-zero internal resistance

Answer

Measures current without affecting the circuit

Answer

Displays the current flowing through the circuit

Answer

Has zero resistance

Question 37

Kirchhoff's voltage law is another fundamental principle in circuit analysis. Which statement correctly describes Kirchhoff's voltage law?

Accepted Answer

The algebraic sum of the voltages around a closed loop is equal to zero

Answer

The current flowing through a resistor is equal to the voltage across the resistor divided by the resistance

Answer

The power dissipated by a resistor is equal to the voltage across the resistor multiplied by the current flowing through the resistor

Question 38

In a simple series circuit, the current (I) passing through each resistor is:

Accepted Answer

The same throughout the circuit

Answer

Proportional to the resistance (R) of the resistor

Answer

Zero unless the circuit is connected to a voltage source

Answer

Inversely proportional to the resistance (R) of the resistor

Question 39

According to Ohm's law, the voltage (V) across a resistor is:

Accepted Answer

Proportional to the current (I) passing through it

Answer

Inversely proportional to the current (I) passing through it

Answer

Equal to the current (I) passing through it

Question 40

Kirchhoff's current law (KCL) states that at any junction in a circuit:

Accepted Answer

The total current flowing into the junction is equal to the total current flowing out

Answer

The current flowing through any branch of the circuit is the same

Answer

The voltage across any point in the circuit is the same

Question 41

In a parallel circuit, the voltage (V) across each resistor is:

Accepted Answer

The same as the voltage across the battery

Answer

Zero unless the resistor is connected to the battery

Answer

Proportional to the resistance (R) of the resistor

Answer

Inversely proportional to the resistance (R) of the resistor

Question 42

When two resistors are connected in parallel, the equivalent resistance (R_eq) is:

Accepted Answer

Less than the smallest resistance

Answer

Equal to the sum of the resistances

Answer

Greater than the largest resistance

Question 43

A capacitor stores energy in the form of:

Accepted Answer

An electric field

Answer

A magnetic field

Answer

Thermal energy

Answer

Kinetic energy

Question 44

The capacitance (C) of a capacitor is directly proportional to:

Accepted Answer

The area of the plates

Answer

The distance between the plates

Answer

The current flowing through the capacitor

Answer

The voltage across the plates

Question 45

In a series RLC circuit, the resonant frequency (f_r) is the frequency at which:

Accepted Answer

The inductive (XL) and capacitive (XC) reactances cancel each other out

Answer

The voltage (V) is maximum

Answer

The current (I) is maximum

Question 46

Which of the following is NOT a property of a conductor?

Accepted Answer

Insulates electric current

Answer

Allows electric current to flow easily

Answer

Has free electrons that can move

Answer

Has a high resistance to electric current

Question 47

In a series circuit, the total resistance is:

Accepted Answer

Equal to the sum of the individual resistances

Answer

Equal to the largest individual resistance

Answer

Zero

Answer

Equal to the smallest individual resistance

Question 48

Ohm's law states that the current through a conductor is:

Accepted Answer

Directly proportional to the voltage applied

Answer

Equal to the voltage applied

Answer

Inversely proportional to the voltage applied

Answer

Independent of the voltage applied

Question 49

Which of the following is a unit of electrical resistance?

Accepted Answer

Ohm

Answer

Volt

Answer

Coulomb

Answer

Ampere

Question 50

Kirchhoff's voltage law states that the algebraic sum of the voltages around a closed loop in a circuit is:

Accepted Answer

Zero

Answer

Equal to the voltage of the source

Answer

Equal to the sum of the resistances in the loop

Question 51

Which of the following is a type of capacitor?

Accepted Answer

Electrolytic capacitor

Answer

Diode

Answer

Inductor

Answer

Resistor

Question 52

What is the function of a diode in an electric circuit?

Accepted Answer

Allows current to flow in only one direction

Answer

Blocks current flow in both directions

Answer

Stores electrical energy

Answer

Increases the voltage of a circuit

Question 53

Which of the following is a type of AC circuit?

Accepted Answer

Capacitive circuit

Answer

Series circuit

Answer

DC circuit

Answer

Parallel circuit

Question 54

What is the resonant frequency of a circuit?

Accepted Answer

The frequency at which the inductive reactance and capacitive reactance are equal

Answer

The frequency at which the current is maximum

Answer

The frequency at which the voltage is maximum

Question 55

Which of the following is an application of electric circuits?

Accepted Answer

Power transmission

Answer

Magnetic levitation

Answer

Chemical reactions

Answer

Heat transfer