Electromagnetics

Question 1

The magnetomotive force per unit length is called the _______

Answer 1

Magnetic field Strength or Magnetizing Force

Question 2

These are passive electronic component which is capable of storing electrical energy in the form of magnetic energy.

Answer 2

Inductors

Question 3

Electric current will produce a magnetic field around the conductor.
Magnetic field does not have specific north or south poles.

Answer 3

Electromagnetic Induction

Question 4

A current generated in a conductor by a changing magnetic field is proportional to the rate of change of the magnetic field.

Answer 4

Inductance

Question 5

What law states that “An induced effect is always such as to oppose the cause that produce it.”

Answer 5

Lenz’ law

Question 6

When coils are closer to each other without shielding, it is possible for the two inductors to couple

Answer 6

Mutual Inductance

Question 7

Types of Electricity

Answer 7

Static and Dynamic

Question 8

It is the movement of electrons from one point to another

Answer 8

Electricity

Question 9

Electricity came from a greek word “_______” which means “Amber”

Answer 9

Elektron

Question 10

As early as 600 B.C. Greeks observed that after rubbing amber with wool, the amber could attract other objects.

This is an “attraction” phenomenon called _______

Answer 10

Amber effect

Question 11

When the number of electrons is equal to the number of protons, the atom is in:

Answer 11

Neutral

Question 12

When the number of electrons is greater than the protons, it is called

Answer 12

Anion

Question 13

When the number of electrons is less than the protons, it is called

Answer 13

Cation

Question 14

It is the Accumulation of electric charges, and it is also known as frictional electricity

Answer 14

Static Electricity

Accumulate meaning stored charges are waiting to be released. Hence, called static electricity (Stationary)

Question 15

It is the flow of electric charges, and it also refers to the so called electric current

Answer 15

Dynamic Electricity

Question 16

“Charge is neither created nor destroyed, it can only be transferred from one system to another”

Answer 16

Law of Conservation of Charge

Question 17

What Coulomb’s law states that “The electrostatic force is directly proportional to the product of the charges”

Answer 17

First Law

Question 18

What Coulomb’s law states that “The electrostatic force is inversely proportional to the square of the distance between the charges”

Answer 18

Second Law

Question 19

A region in which a force would be exerted on other charged particles or objects

Answer 19

Electric field (N/C) (V/m)

Question 20

It is a measure of flow of electric field through a given area

Answer 20

Electric Flux

Question 21

It impedes the flow of AC charges carriers by temporarily storing the energy as an electric field

Answer 21

Capacitors

Question 22

What are the basic configurations of a capacitors?

Answer 22

Two conductors carrying equal but opposite charges

Question 23

It is the ability of a component or circuit to collect and store energy in the form of an electric charge

Answer 23

Capacitance

Question 24

When it comes to Capacitor applications, a job of a _______ is to filter any noise in the power supply, like voltage ripples

Answer 24

Decoupling (Bypass)

Question 25

Because of their specific response time, they are able to block low frequency signals while allowing higher frequencies to pass through.

Answer 25

Filtering

Question 26

Although they can store considerably lower energy compared to a same size battery, their lifespan is much better, and they are capable of delivering energy much faster

Answer 26

Energy storage of a capacitor

Question 27

It is a property possessed by iron, steel and certain other magnetic material, wherein these materials can produce or conduct magnetic lines of forces

Answer 27

Magnetism

Question 28

This makes them interact with electric fields or other magnetic fields

Answer 28

Magnetism

Question 29

The lines from the poles of a magnet always start from _______

Answer 29

North to south

Question 30

However, unlike electric charges which can be separated, magnetic poles _______ be separated

Answer 30

Cannot When a magnet is broken, each piece is found to have a north and south pole

Question 31

What law states that like poles of magnets repel each other while opposite poles attract each other

Answer 31

1st Law of Magnetism

Question 32

What law states that “a magnetic field always tends to arrange itself so that the greatest numbers of line of force are created

Answer 32

2nd law of Magnetism

Question 33

It is the number of magnetic lines of flux that pass through a certain point on a surface

Answer 33

Magnetic flux density

Question 34

It is the ability of a magnetic material to support magnetic field development. It indicates the ease in which an external magnetic field can create a higher magnetic force of attraction in the material

Answer 34

Permeability

Question 35

Not capable of being magnetized

Answer 35

Nonmagnetic Example: Air

Question 36

Materials that are freely magnetized, but the direction is opposite to that of the magnetic field.

Answer 36

Diamagnetic Examples: Bismuth, Antimony, Copper, Zinc, Mercury, Gold, Silver

Question 37

Materials that are weakly attracted to magnets.

Answer 37

Paramagnetic Example: Aluminum, Platinum, Manganese, and Chromium

Question 38

Materials having high susceptibility to magnetization.

Answer 38

Ferromagnetic Examples: Iron, Nickel, Cobalt, and alloy of these metals

Question 39

The amount by which relative permeability differs from unity. Has no unit.

Answer 39

Susceptibility

Question 40

The amount by which relative permeability differs from unity. Has no unit.

Answer 40

Susceptibility

Question 41

The property of a material to allow magnetic flux to be established in a material

Answer 41

Permeance

Question 42

It is magnetism produced by an electric current rather than by a natural magnet. Discovered by _______ in 1819, through a magnetic needle that is deflected at right angles to a wire carrying an electric current

Answer 42

Hans Christian Oersted

Question 43

In 1820, _______ and _______ showed that an electric current can be produced in a circuit either by moving a magnet near the circuit.

Answer 43

Michael Faraday and Joesph Henry

Question 44

Years later, theoretical work by _______ showed that a changing electric field creates a magnetic field

Answer 44

James Clerk Maxwell

Question 45

It is the external force required to serup magnetic flux lines within a magnetic material

Answer 45

Magnetomotive Forcs (mmf)