Electrical Conductivity: A Comprehensive Guide for Engineering Students

Question 1

A material with high electrical conductivity is likely to have which of the following characteristics?

Accepted Answer

Low resistivity

Answer

Good thermal insulating properties

Answer

Transparency to light

Answer

Magnetic properties

Question 2

Which of the following factors does **not** influence the electrical conductivity of a material?

Accepted Answer

Magnetic field

Answer

Temperature

Answer

Impurities

Answer

Crystal structure

Question 3

Which type of material generally exhibits the highest electrical conductivity?

Accepted Answer

Metals

Answer

Insulators

Answer

Semiconductors

Answer

Ceramics

Question 4

What is the relationship between electrical conductivity (σ) and resistivity (ρ)?

Accepted Answer

σ is inversely proportional to ρ

Answer

σ is directly proportional to ρ

Answer

σ is independent of ρ

Answer

σ is exponentially proportional to ρ

Question 5

What is the key difference between intrinsic and extrinsic semiconductors?

Accepted Answer

Extrinsic semiconductors have impurities, while intrinsic semiconductors do not.

Answer

Intrinsic semiconductors have impurities, while extrinsic semiconductors do not.

Answer

Intrinsic semiconductors are used in lasers, while extrinsic semiconductors are used in transistors.

Answer

Extrinsic semiconductors are used in lasers, while intrinsic semiconductors are used in transistors.

Question 6

Which of the following materials is a known superconductor?

Accepted Answer

Mercury

Answer

Copper

Answer

Aluminium

Answer

Gold

Question 7

How does temperature generally affect the electrical conductivity of metals?

Accepted Answer

It decreases with increasing temperature.

Answer

It increases with increasing temperature.

Answer

It remains constant with changing temperature.

Answer

It varies non-linearly with changing temperature.

Question 8

Which material possesses the highest electrical conductivity?

Accepted Answer

Copper

Answer

Aluminum

Answer

Steel

Answer

Rubber

Question 9

What is the SI unit of electrical conductivity?

Accepted Answer

Siemens per meter (S/m)

Answer

Amperes per volt (A/V)

Answer

Ohms per meter (Ω/m)

Answer

Farads per meter (F/m)

Question 10

Which application exemplifies the high electrical conductivity of metals?

Accepted Answer

Electrical wiring

Answer

Electromagnets

Answer

Solar cells

Answer

Transistors

Question 11

Explain the relationship between resistivity and electrical conductivity.

Accepted Answer

Resistivity is inversely proportional to electrical conductivity.

Answer

Resistivity is directly proportional to electrical conductivity.

Answer

No relationship exists between the two.

Answer

They are equivalent to each other.

Question 12

Which material is categorized as a semiconductor?

Accepted Answer

Silicon

Answer

Gold

Answer

Copper

Answer

Insulator

Question 13

How does doping affect the electrical conductivity of a semiconductor?

Accepted Answer

Enhances conductivity

Answer

Impairs conductivity

Answer

No change in conductivity

Answer

Depends on the specific dopant used

Question 14

Identify a key property of electrical insulation materials.

Accepted Answer

Low electrical conductivity

Answer

High electrical conductivity

Answer

High magnetic permeability

Answer

Low thermal conductivity

Question 15

The electrical conductivity of an electrolyte solution is primarily due to the movement of:

Accepted Answer

Ions

Answer

Electrons

Answer

Holes

Answer

Photons

Question 16

The SI unit of electrical conductivity is:

Accepted Answer

Siemens per meter (S/m)

Answer

Farads per meter (F/m)

Answer

Henrys per meter (H/m)

Answer

Ohms per meter (Ω/m)

Question 17

Which of the following materials is considered an excellent electrical insulator?

Accepted Answer

Rubber

Answer

Seawater

Answer

Graphite

Answer

Copper oxide

Question 18

Which device is commonly used to measure the electrical conductivity of materials?

Accepted Answer

Four-point probe

Answer

Voltmeter

Answer

Capacitance meter

Answer

Ammeter

Question 19

Electrical conductivity measures a material's ability to:

Accepted Answer

Allow the flow of electric current

Answer

Generate electric current

Answer

Store electric charge

Answer

Resist the flow of electric current