Master Electrical Concepts: Voltage, Current, Resistance, and Power

Question 1

Which of the following is the SI unit of electrical potential difference?

Accepted Answer

Volt

Answer

Ampere

Answer

Watt

Answer

Ohm

Question 2

The movement of electrical charge is known as:

Accepted Answer

Current

Answer

Voltage

Answer

Resistance

Answer

Power

Question 3

The relationship between voltage, current, and resistance is described by which law?

Accepted Answer

Ohm's Law

Answer

Kirchhoff's Current Law

Answer

Joule's Law

Answer

Faraday's Law

Question 4

What is the SI unit of electrical power?

Accepted Answer

Watt

Answer

Ampere

Answer

Volt

Answer

Ohm

Question 5

Which material listed below is classified as a conductor?

Accepted Answer

Copper

Answer

Rubber

Answer

Glass

Answer

Wood

Question 6

Which physical quantity measures the rate of electrical energy transferred or consumed over time?

Accepted Answer

Power

Answer

Voltage

Answer

Current

Answer

Resistance

Question 7

In the International System of Units (SI), the unit of electrical current is the:

Accepted Answer

Ampere

Answer

Ohm

Answer

Volt

Answer

Watt

Question 8

In an electrical circuit, which component impedes the flow of electric current?

Accepted Answer

Resistor

Answer

Capacitor

Answer

Inductor

Answer

Transformer

Question 9

Which formula correctly calculates the electrical power dissipated in a circuit?

Accepted Answer

P = VI

Answer

P = V/I

Answer

P = I/V

Answer

P = V^2/R

Question 10

Which electrical property measures the ability of a component or circuit to store electrical energy in an electric field?

Accepted Answer

Capacitance

Answer

Inductance

Answer

Resistance

Answer

Voltage

Question 11

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

Accepted Answer

Increase or decrease voltage levels

Answer

Store electrical energy

Answer

Control the flow of current

Answer

Convert alternating current (AC) to direct current (DC)

Question 12

Which of the following correctly describes the difference between an open circuit and a short circuit?

Accepted Answer

Open circuit: infinite resistance; Short circuit: zero resistance

Answer

Open circuit: zero resistance; Short circuit: infinite resistance

Answer

Both open and short circuits have infinite resistance

Answer

Both open and short circuits have zero resistance

Question 13

The main function of an electrical fuse is to:

Accepted Answer

Protect circuits from excessive current flow

Answer

Regulate voltage levels

Answer

Store electrical energy

Answer

Convert AC to DC

Question 14

Voltage is best defined as:

Accepted Answer

The energy stored in an electric field

Answer

The rate of flow of electric charge

Answer

The force that causes electrons to flow

Answer

The resistance to the flow of electric charge

Question 15

Resistance is:

Accepted Answer

The force that opposes the flow of electric charge

Answer

The ease with which an electric current flows

Answer

The amount of energy required to move an electron

Answer

The difference in electric potential between two points

Question 16

Power is defined as:

Accepted Answer

The rate at which electrical energy is transferred

Answer

The amount of electrical energy used in a given time

Answer

The force that causes electrons to flow

Answer

The resistance to the flow of electric charge

Question 17

Ohm's Law relates which electrical quantities?

Accepted Answer

Voltage, current, and resistance

Answer

Power, voltage, and current

Answer

Voltage, resistance, and power

Answer

Current, resistance, and power

Question 18

A circuit that allows current to flow in only one direction is known as a:

Accepted Answer

Series circuit

Answer

Parallel circuit

Answer

Closed circuit

Answer

Open circuit

Question 19

The unit of capacitance is the:

Accepted Answer

Farad

Answer

Ohm

Answer

Ampere

Answer

Volt

Question 20

An inductor stores energy in its:

Accepted Answer

Magnetic field

Answer

Electric field

Answer

Electromagnetic field

Answer

Mechanical field

Question 21

Resonant frequency in a circuit occurs when:

Accepted Answer

Capacitive reactance equals inductive reactance

Answer

Power is maximum

Answer

Voltage is minimum

Answer

Current is zero

Question 22

Which unit is used to measure electrical potential difference?

Accepted Answer

Volt

Answer

Ampere

Answer

Ohm

Answer

Watt

Question 23

How are power, voltage, and current related?

Accepted Answer

Power = Voltage * Current

Answer

Power = Voltage - Current

Answer

Power = Voltage + Current

Answer

Power = Current / Voltage

Question 24

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

Accepted Answer

To protect the circuit from excessive current

Answer

To provide a path for current to flow

Answer

To regulate the voltage in the circuit

Answer

To store electrical energy

Question 25

What is the key difference between AC and DC current?

Accepted Answer

AC current flows in both directions, while DC current flows in one direction.

Answer

AC current flows in one direction, while DC current flows in both directions.

Answer

AC current has a constant voltage, while DC current has a varying voltage.

Answer

AC current has a varying voltage, while DC current has a constant voltage.

Question 26

Which source of electricity is considered renewable?

Accepted Answer

Solar power

Answer

Coal

Answer

Natural gas

Answer

Nuclear power

Question 27

How does the movement of electrons contribute to the generation of electrical current?

Accepted Answer

Electrons flow from negative to positive terminals, creating a current.

Answer

Electrons flow in both directions, canceling each other out and preventing current flow.

Answer

Electrons do not move; it is the electric field that generates current.

Answer

Current is generated by the movement of protons, not electrons.

Question 28

Which of the following is the standard international (SI) unit of voltage?

Accepted Answer

Volt

Answer

Ampere

Answer

Watt

Answer

Ohm

Question 29

A 100-watt light bulb connected to a 120-volt power source has a current of:

Accepted Answer

0.83 amps

Answer

1.2 amps

Answer

10 amps

Answer

120 amps

Question 30

Which of the following is a good conductor of electricity?

Accepted Answer

Copper

Answer

Wood

Answer

Rubber

Answer

Plastic

Question 31

The movement of electrons in a circuit is known as:

Accepted Answer

Current

Answer

Resistance

Answer

Power

Answer

Voltage

Question 32

Which of the following is the SI unit of power in an electrical circuit?

Accepted Answer

Watt

Answer

Ohm

Answer

Volt

Answer

Ampere

Question 33

In a series circuit with a total resistance of 15 ohms and a voltage of 30 volts, the current flowing through the circuit is:

Accepted Answer

2 amps

Answer

10 amps

Answer

5 amps

Question 34

Which of the following is a passive electrical component used to resist the flow of current?

Accepted Answer

Resistor

Answer

Diode

Answer

Transistor

Answer

Capacitor

Question 35

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

Accepted Answer

Protect the circuit from excessive current

Answer

Increase the current flow

Answer

Store energy

Answer

Reduce the voltage

Question 36

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

Accepted Answer

Ampere (A)

Answer

Ohm (Ω)

Answer

Watt (W)

Answer

Volt (V)

Question 37

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

Accepted Answer

Copper

Answer

Plastic

Answer

Glass

Answer

Water

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 store electrical energy

Answer

To maintain constant voltage

Answer

To increase the circuit's resistance

Question 39

Which of the following devices converts mechanical energy into electrical energy?

Accepted Answer

Generator

Answer

Battery

Answer

Capacitor

Question 40

In an electrical circuit, the power dissipated in a resistor is calculated using which formula?

Accepted Answer

P = I² x R

Answer

P = V x I

Answer

P = V² / R

Answer

P = R / I

Question 41

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

Accepted Answer

AC reverses polarity periodically, while DC maintains a constant polarity

Answer

DC is more efficient than AC

Answer

AC has higher voltage than DC

Question 42

Which of the following is an electrical device that utilizes the principle of electromagnetic induction?

Accepted Answer

Transformer

Answer

Battery

Answer

Resistor

Answer

Capacitor

Question 43

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

Accepted Answer

To store electrical energy

Answer

To maintain a stable voltage

Answer

To prevent overcurrent damage

Answer

To increase resistance in the circuit

Question 44

What is the standard unit of electric current in the International System of Units (SI)?

Accepted Answer

Ampere (A)

Answer

Volt (V)

Answer

Ohm (Ω)

Question 45

Which of the following equations represents Ohm's Law, describing the relationship between voltage, current, and resistance in an electrical circuit?

Accepted Answer

Voltage (V) = Current (I) × Resistance (R)

Answer

Current (I) = Voltage (V) / Resistance (R)

Answer

Power (P) = Voltage (V) × Current (I)

Answer

Resistance (R) = Voltage (V) - Current (I)

Question 46

Which material has the ability to allow the flow of electric current?

Accepted Answer

Conductor

Answer

Semiconductor

Answer

Insulator

Question 47

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

Accepted Answer

Limit the flow of current

Answer

Store electrical energy

Answer

Increase the voltage

Question 48

Which type of electrical circuit has only one pathway for the current to flow?

Accepted Answer

Series Circuit

Answer

Mixed Circuit

Answer

Parallel Circuit

Question 49

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

Accepted Answer

Protect the circuit from excessive current

Answer

Regulate the voltage

Answer

Store electrical charge

Question 50

Which of the following is a fundamental property of electricity?

Accepted Answer

Charge

Answer

Volume

Answer

Velocity

Answer

Temperature

Question 51

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

Accepted Answer

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

Answer

DC can be stored in batteries, while AC cannot

Answer

AC has higher voltage than DC

Question 52

Which device converts electrical energy into mechanical energy?

Accepted Answer

Motor

Answer

Battery

Answer

Resistor

Answer

Capacitor

Question 53

What is the SI unit of electrical power?

Accepted Answer

Watt (W)

Answer

Ampere (A)

Answer

Ohm (Ω)

Answer

Volt (V)