Electrical Theory for Construction: Master Electrical Fundamentals

Question 1

In a parallel circuit, the total current flowing through the circuit is equal to the:

Accepted Answer

Sum of the currents flowing through each branch

Answer

Difference of the currents flowing through each branch

Answer

Product of the currents flowing through each branch

Answer

Quotient of the currents flowing through each branch

Question 2

In a series circuit, what is the formula for calculating the total resistance (R_T)?

Accepted Answer

R_T = R1 + R2 + ... + Rn

Answer

R_T = R1 - R2 - ... - Rn

Answer

R_T = R1 * R2 * ... * Rn

Answer

R_T = R1 / R2 / ... / Rn

Question 3

When working with electrical systems, which action is **unsafe**?

Accepted Answer

Touching electrical components with bare hands

Answer

Wearing insulated gloves

Answer

Using a voltage tester to check for live wires

Answer

Shutting off the main power supply before starting work

Question 4

What is the SI unit of measurement for electrical potential difference?

Accepted Answer

Volt

Answer

Ohm

Answer

Ampere

Answer

Watt

Question 5

Which of the following materials is a good conductor of electricity?

Accepted Answer

Copper

Answer

Rubber

Answer

Wood

Answer

Plastic

Question 6

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

Accepted Answer

To protect against overcurrent

Answer

To provide a path for electricity to flow

Answer

To store electrical energy

Answer

To control the direction of current flow

Question 7

Which type of electrical circuit provides only one path for current to flow?

Accepted Answer

Series circuit

Answer

Parallel circuit

Answer

Branch circuit

Answer

Closed circuit

Question 8

What is the main function of a transformer in an electrical system?

Accepted Answer

To increase or decrease voltage

Answer

To store electrical energy

Answer

To protect against short circuits

Answer

To control the flow of current

Question 9

What is the primary purpose of grounding in an electrical system?

Accepted Answer

To provide a path for fault currents

Answer

To reduce electromagnetic interference

Answer

To store electrical energy

Answer

To control the flow of current

Question 10

In an electrical circuit, the relationship between voltage and current is **best** represented by which graph?

Accepted Answer

A straight line with a positive slope

Answer

A straight line with a negative slope

Answer

A parabola

Answer

A circle

Question 11

What is the unit of measure for the flow of electrical charge?

Accepted Answer

Amperes

Answer

Voltage

Answer

Ohms

Answer

Watts

Question 12

Which of the following materials conducts electricity?

Accepted Answer

Metal

Answer

Plastic

Answer

Rubber

Answer

Wood

Question 13

How do you calculate the resistance in an electrical circuit?

Accepted Answer

R = V/I

Answer

R = I/V

Answer

R = V + I

Answer

R = I - V

Question 14

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

Accepted Answer

Control current flow

Answer

Provide insulation

Answer

Store energy

Answer

Convert AC to DC

Question 15

Which component is found in a transformer?

Accepted Answer

Inductor

Answer

Capacitor

Answer

Diode

Answer

Resistor

Question 16

What is the difference between alternating current (AC) and direct current (DC)?

Accepted Answer

AC reverses direction, DC flows in one direction

Answer

DC reverses direction, AC flows in one direction

Answer

AC has higher voltage, DC has lower voltage

Answer

DC has higher voltage, AC has lower voltage

Question 17

Which tool measures electrical voltage?

Accepted Answer

Voltmeter

Answer

Ohmmeter

Answer

Ammeter

Answer

Multimeter

Question 18

What does the acronym 'NEC' stand for?

Accepted Answer

National Electrical Code

Answer

National Engineering Code

Answer

National Electrical Council

Answer

National Electric Committee

Question 19

Before working on an electrical circuit, why is it essential to use a non-contact voltage tester?

Accepted Answer

To avoid the danger of getting an electric shock.

Answer

To check if there is no current flowing in the circuit.

Answer

To measure the resistance of the circuit.

Answer

To find out the polarity of the circuit.

Question 20

The unit of measurement for electrical potential difference is the:

Accepted Answer

Volt (V)

Answer

Ohm (Ω)

Answer

Watt (W)

Answer

Ampere (A)

Question 21

The flow of electric charge in a circuit is known as:

Accepted Answer

Current (I)

Answer

Power (P)

Answer

Resistance (R)

Answer

Voltage (V)

Question 22

Which of the following materials is known for its high electrical conductivity?

Accepted Answer

Copper (Cu)

Answer

Plastic

Answer

Wood

Answer

Rubber

Question 23

The relationship between voltage (V), current (I), and resistance (R) in an electrical circuit is described by:

Accepted Answer

Ohm's Law (V = IR)

Answer

Kirchhoff's Laws

Answer

Faraday's Law

Answer

Coulomb's Law

Question 24

When working with electrical systems, an important safety precaution is to:

Accepted Answer

Always use insulated tools

Answer

Ignore electrical warning signs

Answer

Leave electrical wires exposed

Answer

Work on a wet surface

Question 25

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

Accepted Answer

Protect against excessive current flow

Answer

Decrease resistance

Answer

Increase voltage

Answer

Store electrical energy

Question 26

The formula for calculating electrical power (P) in a circuit is:

Accepted Answer

P = VI

Answer

P = R/I

Answer

P = V/I

Answer

P = I/V

Question 27

The key difference between alternating current (AC) and direct current (DC) is that:

Accepted Answer

AC changes direction periodically, while DC flows in a constant direction

Answer

AC has higher voltage than DC

Answer

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

Question 28

In an electrical system, a transformer primarily functions to:

Accepted Answer

Change the voltage level of an electrical current

Answer

Protect against electrical hazards

Answer

Generate electrical power

Answer

Store electrical energy

Question 29

In an electrical circuit, what is the impact of increased resistance on current flow?

Accepted Answer

Current flow decreases

Answer

Current flow increases significantly

Answer

Current flow remains unaffected

Answer

Current flow changes direction

Question 30

In a series circuit, how does the current change when more resistors are added?

Accepted Answer

Decreases

Answer

Increases

Answer

Stays the same

Answer

Varies depending on the circuit

Question 31

Which physical quantity is measured in Amperes?

Accepted Answer

Electrical current

Answer

Resistance

Answer

Voltage

Answer

Power

Question 32

Which practice is NOT a recommended safety precaution when working with electricity?

Accepted Answer

Using bare hands

Answer

Turning off power before working

Answer

Wearing appropriate protective gear

Answer

Inspecting tools and equipment

Question 33

Which formula represents the relationship between voltage, current, and resistance in a circuit?

Accepted Answer

Voltage = Current × Resistance (Ohm's Law)

Answer

Power = Voltage × Current

Answer

Resistance = Voltage ÷ Current

Answer

Current = Voltage ÷ Resistance

Question 34

What is the primary purpose of a fuse in an electrical system?

Accepted Answer

To protect against excessive current flow

Answer

To store electrical energy

Answer

To regulate voltage levels

Answer

To control the direction of current flow

Question 35

Which material is a good conductor of electricity?

Accepted Answer

Copper

Answer

Wood

Answer

Rubber

Answer

Plastic

Question 36

What is the function of a transformer in an electrical system?

Accepted Answer

To change voltage levels

Answer

To regulate current flow

Answer

To protect against overloads

Answer

To store electrical energy

Question 37

Which unit is used to measure electrical power?

Accepted Answer

Watt

Answer

Ohm

Answer

Ampere

Answer

Volt

Question 38

Which law describes the relationship between voltage, current, and resistance in a circuit?

Accepted Answer

Ohm's Law

Answer

Joule's Law

Answer

Faraday's Law

Answer

Kirchhoff's Voltage Law

Question 39

In a simple series circuit with a battery and two resistors, what happens to the current through one resistor if the other resistor is removed?

Accepted Answer

It increases

Answer

It decreases

Answer

It remains the same

Answer

It reverses direction

Question 40

Which of the following factors does NOT affect electrical resistance?

Accepted Answer

Current

Answer

Length

Answer

Material

Answer

Cross-sectional area

Question 41

Which of the following is a closed path that allows electricity to flow?

Accepted Answer

Circuit

Answer

Source

Answer

Insulator

Answer

Load

Question 42

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

Accepted Answer

To prevent circuit damage due to excessive current

Answer

To increase circuit efficiency

Answer

To store electrical energy

Answer

To regulate voltage levels

Question 43

Which of the following types of circuits has a single path for current to flow?

Accepted Answer

Series

Answer

Mixed

Answer

Parallel

Answer

Wheatstone bridge

Question 44

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

Accepted Answer

To change the voltage level

Answer

To regulate current flow

Answer

To break electrical circuits

Answer

To store electrical energy

Question 45

Which of the following is a unit of electrical power?

Accepted Answer

Watt

Answer

Ampere

Answer

Joule

Answer

Farad

Question 46

What is the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit?

Accepted Answer

V = I x R

Answer

V = R x I

Answer

I = V - R

Answer

R = V + I

Question 47

What is the SI unit of electric current?

Accepted Answer

Ampere (A)

Answer

Coulomb (C)

Answer

Ohm (Ω)

Answer

Volt (V)

Question 48

Which unit is used to measure the amount of electrical potential difference or voltage?

Accepted Answer

Volt (V)

Answer

Ampere (A)

Answer

Ohm (Ω)

Question 49

Select the option that is NOT a fundamental electrical circuit type.

Accepted Answer

Mesh

Answer

Series

Answer

Parallel

Answer

Bridge

Question 50

Which formula is used to calculate electrical power?

Accepted Answer

Power (W) = Voltage (V) x Current (A)

Answer

Power (W) = Current (A) / Voltage (V)

Answer

Power (W) = Voltage (V) + Current (A)

Question 51

Which material has high electrical conductivity?

Accepted Answer

Copper (Cu)

Answer

Rubber

Answer

Plastic

Answer

Wood

Question 52

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

Accepted Answer

To interrupt the circuit and prevent damage in the case of excessive current flow.

Answer

To increase current flow

Answer

To regulate voltage levels

Answer

To store electrical energy

Question 53

Which advantage of alternating current (AC) over direct current (DC) makes it suitable for long-distance power transmission?

Accepted Answer

AC can be efficiently transmitted over long distances with minimal power loss.

Answer

AC is easier to convert between different voltage levels.

Answer

AC produces higher voltages than DC.

Question 54

Identify a potential drawback of using parallel circuits.

Accepted Answer

Troubleshooting parallel circuits can be more challenging due to multiple current paths.

Answer

Parallel circuits require more power than series circuits.

Answer

Parallel circuits are less efficient than series circuits.

Question 55

Explain the relationship between resistance and current in an electrical circuit.

Accepted Answer

Resistance is inversely proportional to current, meaning that as resistance increases, current decreases, and vice versa.

Answer

Resistance is equal to current.

Answer

Resistance is not related to current.

Answer

Resistance is directly proportional to current.