Electrical Circuits: Master the Fundamentals of Electricity

Question 1

In a series circuit, what is the total resistance (R) of the circuit?

Accepted Answer

The sum of the individual resistances (R1 + R2 + ...)

Answer

The average of the individual resistances ((R1 + R2 + ...) / n)

Answer

The smallest individual resistance (min(R1, R2, ...))

Question 2

In a series circuit, the resistors are connected in a way that forces the current to flow through:

Accepted Answer

A single path

Answer

Multiple parallel paths

Answer

Only one resistor at a time

Answer

Parallel branches

Question 3

Calculate the total resistance of a circuit with three resistors connected in parallel: a 10-ohm resistor, a 15-ohm resistor, and a 20-ohm resistor.

Accepted Answer

5 ohms

Answer

10 ohms

Answer

15 ohms

Question 4

A characteristic of a short circuit is:

Accepted Answer

Low resistance and high current.

Answer

High resistance and low current.

Answer

High voltage and low current.

Question 5

The primary purpose of a fuse in an electrical circuit is to:

Accepted Answer

Protect against excessive current.

Answer

Increase the current flow.

Answer

Act as a conductor.

Question 6

In a typical household lighting system, the type of circuit used is a:

Accepted Answer

Parallel circuit

Answer

Series circuit

Answer

Combination circuit

Question 7

The distinction between an open circuit and a closed circuit is that:

Accepted Answer

In a closed circuit, current flows freely, while in an open circuit, it is blocked.

Answer

In an open circuit, current flows freely, while in a closed circuit, it is blocked.

Answer

An open circuit has high resistance, whereas a closed circuit has low resistance.

Question 8

The primary function of a resistor in an electrical circuit is to:

Accepted Answer

Control the flow of current.

Answer

Increase the voltage.

Answer

Store energy.

Question 9

In a parallel circuit, the total resistance is calculated using the formula:

Accepted Answer

R_total = 1 / (1/R1 + 1/R2 + ... + 1/Rn)

Answer

R_total = R1 + R2 + ... + Rn

Answer

R_total = (R1 * R2 * ... * Rn) / (R1 + R2 + ... + Rn)

Answer

R_total = √(R1^2 + R2^2 + ... + Rn^2)

Question 10

In a series circuit, the current through each resistor is:

Accepted Answer

The same for all resistors

Answer

Different for each resistor

Answer

Inversely proportional to the resistance of each resistor

Answer

Directly proportional to the resistance of each resistor

Question 11

Which of the following is a characteristic of a series circuit?

Accepted Answer

The total voltage is equal to the sum of the individual voltage drops

Answer

The total current is equal to the sum of the individual currents

Answer

The resistance of the circuit is greater than the sum of the individual resistances

Answer

The voltage across each resistor is different

Question 12

The power dissipated in a resistor is given by:

Accepted Answer

P = I^2R

Answer

P = V/I

Answer

P = I/V

Answer

P = V^2/R

Question 13

Ohm's Law states that:

Accepted Answer

The current through a resistor is directly proportional to the voltage across the resistor

Answer

The current through a resistor is inversely proportional to the voltage across the resistor

Answer

The current through a resistor is proportional to the square of the voltage across the resistor

Answer

The current through a resistor is proportional to the cube of the voltage across the resistor

Question 14

Which of the following is NOT a type of electrical circuit?

Accepted Answer

Radial circuit

Answer

Series circuit

Answer

Parallel circuit

Answer

Combination circuit

Question 15

When two resistors are connected in parallel, their combined resistance is:

Accepted Answer

Less than the resistance of either individual resistor

Answer

Greater than the resistance of either individual resistor

Answer

Equal to the resistance of either individual resistor

Answer

Double the resistance of either individual resistor

Question 16

Which of the following is a unit of electrical resistance?

Accepted Answer

Ohm

Answer

Ampere

Answer

Volt

Answer

Coulomb

Question 17

According to Kirchhoff's Current Law, what is the relationship between the sum of the currents entering a junction and the sum of the currents leaving that junction?

Accepted Answer

The sum of the currents entering the junction is equal to the sum of the currents leaving the junction.

Answer

The sum of the currents entering the junction is greater than the sum of the currents leaving the junction.

Answer

The sum of the currents entering the junction is less than the sum of the currents leaving the junction.

Question 18

In a series circuit, the total resistance is equal to:

Accepted Answer

The sum of the resistances of all the resistors

Answer

The resistance of any individual resistor

Answer

The difference between the resistances of the resistors

Answer

Zero

Question 19

In a combination circuit, the total current is:

Accepted Answer

Equal to the sum of the currents in each branch

Answer

Less than the current in any individual branch

Answer

Greater than the current in any individual branch

Answer

Equal to the current in the smallest branch

Question 20

What is the voltage drop across a resistor in a series circuit?

Accepted Answer

Proportional to the resistance of the resistor

Answer

Equal to the voltage of the power source

Answer

Inversely proportional to the resistance of the resistor

Answer

Independent of the resistance of the resistor

Question 21

Which of the following tools is used to measure resistance?

Accepted Answer

Ohmmeter

Answer

Ammeter

Answer

Voltmeter

Answer

Capacitance meter

Question 22

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

Accepted Answer

To limit the flow of current

Answer

To block the flow of current

Answer

To increase the flow of current

Answer

To store energy

Question 23

Which of the following types of loads is characterized by a high resistance and low current draw?

Accepted Answer

Resistive load

Answer

Inductive load

Answer

Capacitive load

Answer

Non-linear load

Question 24

In a series circuit, the overall resistance is:

Accepted Answer

Equal to the sum of the resistances of all components

Answer

Greater than the resistance of any individual component

Answer

Less than the resistance of any individual component

Answer

Zero

Question 25

In a parallel circuit, the total current is:

Accepted Answer

Equal to the sum of the currents through all branches

Answer

Greater than the current through any individual branch

Answer

Less than the current through any individual branch

Answer

Zero

Question 26

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

Accepted Answer

Transistor

Answer

Resistor

Answer

Capacitor

Answer

Inductor

Question 27

The primary function of a fuse in an electrical circuit is to:

Accepted Answer

Safeguard the circuit from excessive current

Answer

Regulate the voltage within the circuit

Answer

Store electrical energy within the circuit

Answer

Control the flow of current throughout the circuit

Question 28

The SI unit of electrical current is the:

Accepted Answer

Ampere

Answer

Volt

Answer

Ohm

Answer

Watt

Question 29

The formula used to calculate the power dissipated by a resistor is:

Accepted Answer

P = I^2R

Answer

P = IV

Answer

P = V^2R

Answer

P = I/R

Question 30

The primary purpose of a capacitor in an electrical circuit is to:

Accepted Answer

Store electrical energy

Answer

Regulate the voltage within the circuit

Answer

Control the flow of current throughout the circuit

Answer

Protect the circuit from excessive current

Question 31

Ohm's Law states the relationship between:

Accepted Answer

Voltage, current, and resistance

Answer

Power, voltage, and resistance

Answer

Current, power, and resistance

Answer

Voltage, power, and current

Question 32

In an electrical circuit, the purpose of a ground is to:

Accepted Answer

Provide a path for current to return to its source

Answer

Protect the circuit from voltage fluctuations

Answer

Store electrical energy for later use

Answer

Control the flow of current through specific components

Question 33

Which of the following is the unit of electric current?

Accepted Answer

Ampere

Answer

Volt

Answer

Watt

Answer

Ohm

Question 34

In Ohm's Law, the relationship between voltage, current, and resistance is expressed as:

Accepted Answer

Voltage = Current × Resistance

Answer

Voltage = Resistance + Current

Answer

Current = Voltage - Resistance

Answer

Resistance = Current / Voltage

Question 35

In a series circuit, the total resistance is:

Accepted Answer

Equal to the sum of individual resistances

Answer

Greater than the sum of individual resistances

Answer

Less than the sum of individual resistances

Question 36

In a parallel circuit, the total current is:

Accepted Answer

Equal to the sum of individual currents

Answer

Greater than the sum of individual currents

Answer

Less than the sum of individual currents

Answer

Independent of the individual currents

Question 37

Which type of circuit has multiple pathways for current to flow?

Accepted Answer

Parallel Circuit

Answer

Series Circuit

Answer

Open Circuit

Answer

Closed Circuit

Question 38

What is the primary function of a fuse in an electrical circuit?

Accepted Answer

To protect the circuit from excessive current

Answer

To amplify current

Answer

To regulate voltage

Answer

To store electrical energy

Question 39

Which of the following factors affects the resistance of a conductor?

Accepted Answer

Material, length, cross-sectional area

Answer

Voltage, current, power

Answer

Temperature, humidity, insulation

Answer

Shape, color, weight

Question 40

What is the fundamental difference between AC and DC current?

Accepted Answer

AC reverses direction periodically, while DC flows in one direction

Answer

AC has higher voltage than DC

Answer

DC is used in batteries, while AC is used in power lines

Question 41

Which component is used to manually control the flow of current in a circuit?

Accepted Answer

Switch

Answer

Capacitor

Answer

Resistor

Answer

Diode

Question 42

What is the primary function of a transformer in an electrical circuit?

Accepted Answer

To change the voltage or current levels

Answer

To store energy

Answer

To protect the circuit from surges

Question 43

In a closed loop circuit, what does Kirchhoff's Voltage Law state about the total voltage changes?

Accepted Answer

They add up to zero

Answer

They equal the voltage of the power source

Answer

They equal the resistance of the circuit

Question 44

Which circuit configuration results in the highest total resistance?

Accepted Answer

Two resistors in series

Answer

Two resistors in parallel

Answer

A single resistor

Answer

Three resistors in parallel

Question 45

Which factors influence the current flow in a circuit?

Accepted Answer

Voltage, resistance, and circuit configuration

Answer

Circuit configuration only

Answer

Voltage only

Answer

Resistance only

Question 46

What is the primary function of a fuse in an electrical circuit?

Accepted Answer

Protect the circuit from excessive current flow

Answer

Store energy

Answer

Regulate voltage

Answer

Increase current flow

Question 47

Which safety measure is crucial when working with electrical circuits?

Accepted Answer

Always disconnect the power before commencing work

Answer

Handle wires with bare hands

Answer

Work in wet environments

Question 48

What distinguishes AC and DC current?

Accepted Answer

AC current periodically reverses direction, while DC current flows consistently in one direction

Answer

AC current carries higher voltage than DC current

Answer

DC current is more efficient than AC current

Question 49

Which of the following is NOT a core component of a basic electrical circuit?

Accepted Answer

Capacitor

Answer

Load

Answer

Resistor

Answer

Power source

Question 50

If one resistor breaks in a series circuit, what happens to the flow of current?

Accepted Answer

The current stops flowing through the entire circuit.

Answer

The current continues flowing only through the working resistors.

Answer

The current increases through the working resistors.

Answer

The current splits and flows through other paths.

Question 51

What is the total resistance when two 10-ohm resistors are connected in parallel?

Accepted Answer

5 ohms

Answer

15 ohms

Answer

20 ohms

Answer

10 ohms

Question 52

Which statement is NOT true about a parallel circuit?

Accepted Answer

The current is the same through each branch.

Answer

The voltage is the same across each branch.

Answer

Each component has its own path for current flow.

Answer

A fault in one branch doesn't affect the other branches.

Question 53

A circuit has two resistors connected in series: one 20-ohm and one 30-ohm. What is the total resistance?

Accepted Answer

50 ohms

Answer

25 ohms

Answer

10 ohms

Answer

600 ohms

Question 54

What is the best description of a combination circuit?

Accepted Answer

A circuit with both series and parallel connections.

Answer

A circuit with only resistors.

Answer

A circuit with more than one voltage source.

Answer

A circuit with only one path for current.

Question 55

In a combination circuit's parallel section, what is true about the voltage across each branch?

Accepted Answer

The voltage is the same across each branch.

Answer

The voltage is lower in the branch with higher resistance.

Answer

The voltage is different across each branch.

Answer

The voltage is higher in the branch with higher resistance.

Question 56

A circuit has a 12-volt battery and a 6-ohm resistor. What is the current flowing through the resistor?

Accepted Answer

2 amps

Answer

6 amps

Answer

18 amps

Answer

1 amp

Question 57

A circuit has a 12-volt battery and a current of 3 amps flowing through it. What is the total resistance of the circuit?

Accepted Answer

4 ohms

Answer

15 ohms

Answer

1 amp

Answer

36 ohms

Question 58

Which statement is TRUE about a series circuit?

Accepted Answer

The current is the same through each component.

Answer

The total resistance is the average of the individual resistances.

Answer

The voltage is the same across each component.

Answer

The current is divided equally among the components.

Question 59

A circuit has three resistors in parallel: 5 ohms, 10 ohms, and 20 ohms. What is the total resistance of the circuit?

Accepted Answer

Less than 5 ohms

Answer

Exactly 15 ohms

Answer

Exactly 35 ohms

Answer

More than 20 ohms