Electrical Properties of Materials: Master the Fundamentals for Engineers

Question 1

In an electrical circuit, which parameter measures how easily electric current flows through a material?

Accepted Answer

Electrical conductivity

Answer

Resistance

Answer

Inductance

Question 2

Which material exhibits exceptionally high electrical conductivity at room temperature?

Accepted Answer

Copper

Answer

Diamond

Answer

Polyethylene

Answer

Silicon

Question 3

The unit of electrical conductivity is:

Accepted Answer

Siemens per meter

Answer

Ohm per meter

Answer

Farad per meter

Answer

Henry per meter

Question 4

Which of the following materials is considered a good insulator?

Accepted Answer

Rubber

Answer

Copper

Answer

Silicon

Answer

Silver

Question 5

Superconductivity is a phenomenon that occurs when a material:

Accepted Answer

Loses all electrical resistance

Answer

Gains infinite electrical resistance

Answer

Becomes magnetic

Answer

Generates an electric field

Question 6

The band gap in a semiconductor is the:

Accepted Answer

Energy difference between the valence band and the conduction band

Answer

Energy required to create a free electron

Answer

Energy lost when an electron recombines

Answer

Energy stored in a capacitor

Question 7

Which of the following factors does NOT influence the dielectric properties of a material?

Accepted Answer

Current

Answer

Temperature

Answer

Frequency

Answer

Material composition

Question 8

What is the primary purpose of insulators?

Accepted Answer

Preventing current flow

Answer

Allowing current flow

Answer

Storing electrical energy

Answer

Generating electricity

Question 9

Which material is a proficient conductor but a poor insulator?

Accepted Answer

Copper

Answer

Rubber

Answer

Ceramic

Answer

Glass

Question 10

How is the dielectric constant related to the capacitance of a capacitor?

Accepted Answer

Capacitance is directly proportional to the dielectric constant

Answer

Capacitance is inversely proportional to the dielectric constant

Answer

Capacitance is equal to the dielectric constant

Answer

Capacitance is not related to the dielectric constant

Question 11

What term describes a material with a high resistance to electric current flow?

Accepted Answer

Insulator

Answer

Conductor

Answer

Semiconductor

Answer

Superconductor

Question 12

Which semiconductor property is NOT characteristic?

Accepted Answer

High thermal conductivity

Answer

Variable electrical conductivity

Answer

Crystalline structure

Answer

Low electrical conductivity at low temperatures

Question 13

What is the fundamental distinction between a conductor and an insulator?

Accepted Answer

Conductors possess free electrons, while insulators do not.

Answer

Insulators possess free electrons, while conductors do not.

Answer

Conductors exhibit higher resistance than insulators.

Answer

Insulators exhibit higher resistance than conductors.

Question 14

Which factor is crucial in determining a material's dielectric constant?

Accepted Answer

Polarizability of molecules

Answer

Material density

Answer

Material temperature

Answer

Material thickness

Question 15

What is the phenomenon where a material exhibits zero electrical resistance below a specific critical temperature?

Accepted Answer

Superconductivity

Answer

Conductivity

Answer

Insulation

Answer

Semiconductivity

Question 16

Which application utilizes the semiconducting properties of materials?

Accepted Answer

Transistors

Answer

Electrical wiring insulation

Answer

Capacitors

Answer

Superconducting magnets

Question 17

Which method is used to enhance the electrical conductivity of a semiconductor?

Accepted Answer

Doping

Answer

Annealing

Answer

Quenching

Answer

Tempering

Question 18

What is the primary function of a dielectric material in a capacitor?

Accepted Answer

Preventing electricity flow

Answer

Conducting electricity

Answer

Storing electrical energy

Answer

Generating electrical energy

Question 19

Classify the following material as a conductor, semiconductor, or insulator: Silicon

Accepted Answer

Semiconductor

Answer

Conductor

Answer

Insulator

Question 20

What is the SI unit used to measure resistivity?

Accepted Answer

Ohm-meter (Ω·m)

Answer

Henry-meter (H·m)

Answer

Siemens-meter (S·m)

Answer

Farad-meter (F·m)

Question 21

Which factor significantly influences the electrical conductivity of a semiconductor?

Accepted Answer

Temperature

Answer

Magnetic field

Answer

Light intensity

Answer

Pressure

Question 22

Identify the primary mechanism responsible for electrical conduction in metals.

Accepted Answer

Movement of free electrons

Answer

Exciton generation

Answer

Diffusion of ions

Answer

Drift of holes

Question 23

Which property characterizes superconductors?

Accepted Answer

Zero electrical resistance below a critical temperature

Answer

Low thermal conductivity

Answer

High magnetic permeability

Question 24

How does the permittivity of a material affect its ability to store electrical energy?

Accepted Answer

Higher permittivity leads to increased capacitance

Answer

Lower permittivity results in higher electrical conductivity

Answer

Higher permittivity reduces the dielectric strength

Question 25

Which material possesses the highest dielectric strength?

Accepted Answer

Diamond

Answer

Water

Answer

Paper

Question 26

What is the practical significance of the piezoelectric effect?

Accepted Answer

It enables materials to generate electrical charges when subjected to mechanical stress

Answer

It reduces the magnetic susceptibility of materials

Answer

It increases the electrical resistivity of materials

Question 27

Identify the material that exhibits ferroelectricity.

Accepted Answer

Barium titanate

Answer

Copper

Answer

Silicon