Inductors

Question 1

The inductor is a component that has the ability to ___________.

Answer 1

The inductor is a component that has the ability to concentrate a magnetic field.

Question 2

To induce voltage in an inductor, the current flow must be____?

Answer 2

increasing or decreasing

Question 3

Increasing current in a circuit causes an expanding magnetic field in the inductor.

What is the effect of a expanding magnetic field by the inductor in the circuit?

Answer 3

The expanding magnetic field creates another voltage by the inductor that is opposite the applied voltage. The induced voltage opposes the increasing current flow and total circuit current remains at 0 Amps.

Question 4

If an AC voltage is applied to an inductor the current is constantly _____ and the inductor is constantly _________.

Answer 4

If an AC voltage is applied to an inductor the current is constantly changing and the inductor is constantly opposing circuit current.

Question 5

As AC current increases, the inductor _____ circuit current. As current decreases, the inductor ______ circuit current.

Answer 5

As AC current increases, the inductor decreases circuit current. As current decreases, the inductor increases circuit current.

Question 6

What are the three classifications of inductors (L)?

Answer 6

Air Core

• used as frequency filters and to keep circuit current at a constant level.
• The schematic symbol is a wavy line.

Iron Core

• values are larger due to the conductive material in the core.
• iron core enables the inductor to produce a larger magnetic field.
• Schematic symbol includes two lines indicating the iron core.

Variable

• Varying values of inductance used in transmitters and receivers.
• Schematic symbol contains an arrow indicating an adjustment.

Question 7

What is Inductance?

Answer 7

Inductance is the ability of a conductor to induce (generate) voltage when “cut” by magnetic flux.

Question 8

What is the symbol for inductance?

Answer 8

The symbol for inductance is L.

Question 9

What is the basic unit of inductance? How is it measured?

Answer 9

The henry (H) is the basic unit of inductance.

Question 10

A millihenry is equivalen to what?

Answer 10

One-thousandth of a henry or 1 x 10^-3

Question 11

A microhenry is equivalen to what?

Answer 11

One-millionth of a henry or 1 times 10^-6.

Question 12

What are the factors that determe inductance?

Answer 12

Number of turns of wire on coil

Distance between windings

Cross-sectional area of core

Permeability of core

Question 13

What is permeability?

Answer 13

The ease with which a material can be magnetized.