Question 1

____ is a measure of a material's ability to become magnetized.&#10;A) Inductance&#10;B) Flux&#10;C) Permeability&#10;D) Reluctance

Accepted Answer

Permeability is a measure of a material's ability to become magnetized. Specifically, it measures the degree of magnetization that can be induced in the material when a magnetic field is applied. The higher the permeability, the more easily the material can become magnetized.

Question 2

____ Law states that an induced voltage or current opposes the motion that causes it.&#10;A) Fleming's&#10;B) Seebeck's&#10;C) Lenz's&#10;D) Ohm's

Accepted Answer

This statement describes Lenz's Law. Fleming's Law describes the direction of the induced current in a conductor when it moves in a magnetic field, Seebeck's Law describes the relationship between temperature differences and electric potentials in a circuit, and Ohm's Law describes the relationship between voltage, current, and resistance in a circuit.

Question 3

The amount of magnetism left in a material after the magnetizing force has stopped is called ____ magnetism.&#10;A) coercive&#10;B) residual&#10;C) saturated&#10;D) reluctant

Accepted Answer

The amount of magnetism left in a material after the magnetizing force has stopped is called residual magnetism.

Question 4

Magnetic lines of force are called ____.&#10;A) poles&#10;B) turns&#10;C) flux&#10;D) current

Accepted Answer

Magnetic lines of force are also referred to as magnetic flux.

Question 5

A piece of nonmagnetized metal has its molecules in a state of disarray.

Accepted Answer

In order for a material to be magnetized, its molecules need to be aligned in the same direction. If they are in a state of disarray, the material is not magnetized.

Question 6

The principle of magnetic ____ states that whenever a conductor cuts through magnetic lines of flux, a voltage is induced into the conductor.&#10;A) induction&#10;B) resistance&#10;C) flux&#10;D) generation

Accepted Answer

The principle described in the sentence is exactly the principle of electromagnetic induction, which is choice A. Resistance and generation have no direct connection to the described principle. While flux is involved, it is not a principle itself but rather a concept relevant to the principle of induction.

Question 7

Examples of ____ materials are iron, nickel, cobalt, and manganese.&#10;A) nonmagnetic&#10;B) ferromagnetic&#10;C) paramagnetic&#10;D) diamagnetic

Accepted Answer

Ferromagnetic materials have a strong attraction to magnetic fields, and the materials listed (iron, nickel, cobalt, and manganese) are all examples of ferromagnetic materials.

Question 8

Inductance is measured in units called the ____.&#10;A) weber&#10;B) henry&#10;C) ampere&#10;D) ohm

Accepted Answer

Inductance is measured in henrys (H), named after the scientist Joseph Henry who contributed to the development of electromagnetic theory. Weber (Wb) is a unit of magnetic flux, ampere (A) is a unit of electric current, and ohm (Ω) is a unit of resistance.

Question 9

The exponential curve is divided into ____ time constants.&#10;A) five&#10;B) six&#10;C) seven&#10;D) eight

Accepted Answer

An exponential curve is typically divided into five time constants, which is the time it takes for the system to reach approximately 99.3% of its final value.

Question 10

If the direction of motion is reversed in a coil, the polarity of the induced current stays the same.

Accepted Answer

When the direction of motion is reversed in a coil, the polarity of the induced current also reverses. This is known as Lenz's law.

Question 11

In the CGS system of measurement, one magnetic line of force is known as a gauss.

Accepted Answer

The answer of In the CGS system of measurement, one...

Question 12

The exponential curve can often be found in nature.

Accepted Answer

The answer of The exponential curve can often be found...

Question 13

____ are magnets that do not require any power or force to maintain their field.&#10;A) Natural magnets&#10;B) Manmade magnets&#10;C) Electromagnets&#10;D) Permanent magnets

Accepted Answer

The answer of ____ are magnets that do not require...

Question 14

In magnetic measurement, ____ lines of flux are equal to one weber (Wb)&#10;A) 100,000&#10;B) 1,000,000&#10;C) 10,000,000&#10;D) 100,000,000

Accepted Answer

The answer of In magnetic measurement, ____ lines of flux...

Question 15

In the left-hand generator rule, the thumb points in the direction of ____.&#10;A) current&#10;B) voltage&#10;C) thrust&#10;D) flux

Accepted Answer

The answer of In the left-hand generator rule, the thumb...

Question 16

The induced voltage is ____ to the rate of change of current.&#10;A) proportional&#10;B) not related&#10;C) inversely proportional&#10;D) exponentially related

Accepted Answer

The answer of The induced voltage is ____ to the...

Question 17

The strength of an electromagnet is proportional to its ____.&#10;A) flux-amperes&#10;B) ampere-turns&#10;C) flux-turns&#10;D) ampere-ohms

Accepted Answer

The answer of The strength of an electromagnet is proportional...

Question 18

Iron core inductors ____.&#10;A) are not susceptible to hysteresis loss&#10;B) can be used for high-frequency applications&#10;C) do not provide a good magnetic path&#10;D) produce more inductance with fewer turns than air core inductors

Accepted Answer

The answer of Iron core inductors ____.&#10;A) are not susceptible...

Question 19

In the MKS system, the main unit of magnetic measurement is the ____.&#10;A) dyne&#10;B) gauss&#10;C) gilbert&#10;D) unit magnetic pole

Accepted Answer

The answer of In the MKS system, the main unit...

Question 20

An increase in current flow will cause a decrease in magnetic field strength.

Accepted Answer

The answer of An increase in current flow will cause...

Deck 4: Magnetism