Chapter 3-5 Basic Electonics

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The north magnetic pole of a compass needle is attracted to the _____ magnetic pole of the earth

South

Insulators are the only materials that can hold _______ stationary

Static

If an object is placed in the field of a strong electromagnet connected to an AC line, the object will be _______

Demagnetized

Lodestone is a name for a naturally occurring magnetic material that is also called _________

Leading stones

To locate the north pole of an electromagnet, use the _____-hand rule

Left

What is indicated by the 4th color band on a resistor?

Multiplier band

How many color bands are used on resistors that have a tolerance of +_20 percent?

3

The strength of ab electromagnet is primarily proportional to its _________

Ampere-turns

Static electricity refers to electrons that ______ moving

Aren't

What type of fixed resistor is made from a compound of carbon graphite and resin bonding material?

Carbon resistor

The angular difference between true north and magnetic north is known as the angle of _________

Declination

In the english system of measure, magnetic strength is measured in terms of ______

Flux density

The measure of a materials ability to be magnetized is called ________

Flux or mmf

If a thundercloud has a positive charge, the current in the lightening bolt will flow from the _______________

Ground to cloud

Man-made permanent magnets retain their magnetism _____ than other natural magnets

Longer

The shock that results from walking across a carpet and touching a doorknob is an example of a(n) _______ static charge

Nuisance

What is another term for a variable resistor?

Potentiometer

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

Residual

The measure of a materials resistance to magnetism is known as __________

Resistance

A variable resistor with 3 terminals is called a _______

Rheostat

When a magnetic materials molecules are all lined up, and increases in current flow no longer cause increase in magnetic field strength, the material has reached __________

Saturation

Selenium is a(n)

Semiconductor

The static charge sometimes used during spray painting is an example of a(n)______ static charge

Useful

A resistor whose values can be varied over a range of values is called a _______ resistor

Variable

Resistors functioning as _______ are used in applications involving field-effect transistors (FETs) and multi-range voltmeter circuits.

Voltage dividers

What type of fixed resistor is made by winding a piece of resistive wire around a ceramic core?

Wire wound resistor

What type of resistors are generally used when a high power rating is needed?

Wire wound resistors

What type of fixed resistor is made by applying a film of carbon to a ceramic rod?

carbon film resistor

Magnetic lines of force are referred to as ________

flux

In the english system, the total force producing a magnetic field is the _______

magnetomotive force

The________of a resistor indicates the plus and minus limits of a resistors ohmic value

tolerance

A basic law of magnetism states that unlike poles _____ and like poles _______

Attract and repel

The regions formed in the molecular structure of magnetic metals are sometimes called magnetic ___________

Domains/molecules

What type of magnet depends on flowing current to produce a magnetic field?

Electromagnets

Magnetism can be explained in terms of _________ spin patterns

Electron

The 3 substances that form natural magnets are

Ferromagnetic, Paramagnetic, and Diamagnetic

The precipitator uses a high-voltage DC power supply to provide a set of wires with a positive charge and a set of plates with a _______ charge

Negative

Within a lightning bolt, current flows ______

Negative to positive

Bringing a charged test object near the ball of a charged electroscope causes the leaves to move closer together. This indicates that the test object charge is the_______ polarity as the electroscope charge.

Opposite

What type of resistors can only have one ohmic value?

Fixed

What color used as the multiplier band means to divide the combined first two number by 10?

Gold

Electrostatic charges occur on _______

Insulator materials

If a permanent magnet is cut into pieces, each piece ________ a separate magnet

Is

A lightning protection device that is grounded at one end is called a(n)___________

Lightning rod

In a clothes dryer, the greatest static charges generally are built up on _______ fabrics

Man-made

What type of fixed resistor is made by applying a film of metal to a ceramic rod in a vaccum?

Metal film resistor

What type of fixed resistor is made by combining metal with glass and then applying it to a ceramic base as a thick film?

Metal glaze resistor

What type of resistor operates by moving the wiper arm with a screw of some number of turns?

Multi turn

What type of magnets do not require any power or force to maintain their field?

Permanent magnets

The semiconductor material used as a coating on copy machine drums is __________

Selenium


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