Abeka Grade 9 Science Test 10

domain

A group of aligned atoms having a single magnetic field is a ________.

permanent

A magnet made from a magnetically hard substance is a _________ magnet.

paramagnetic

A material that has only one unpaired electron per atom and is weakly attracted to magnets is __________.

attract

According to the law of electric charges, opposite charges ______ each other.

uniform field

An electric field in which the strength is evenly distributed throughout, as between plates of opposite charge, is an __________.

negative

An excess of electrons causes a _________ charge.

magnetic equator

An imaginary circle around the earth halfway between the magnetic poles is the __________________.

neutral

An object that has no overall electric charge is ________.

static

Electric charges are considered _________ electricity.

Electric charge always moves to the outside of a charged object. Even if a Faraday suit develops a strong electric charge, the charge will remain on the outside instead of shocking the wearer (inside).

Explain why a Faraday suit, which encloses the wearer's entire body in a mesh of conducting material, can protect someone from being electrocuted while working on power lines.

quadrupled

If the distance between two magnets is halved, what happens to the strength of the magnetic force between them?

doubled

If the number of loops in an electromagnet's coil is doubled, the strength of the electromagnet is _________.

doubled

If the strength of a magnet doubles, what happens to the force between it and another magnet?

5.00 N

If two charged objects have a 125 N force between them when they are 3.00 m apart, what force exists between them when they are 15.0 m apart?

induction

Imparting a charge by bringing a charged object near, but not touching, a neutral object is charging by _______.

positive streamer

In a lightning bolt, the downward flow of charge from the cloud attracts an upward flow of charge from the ground called the _____.

De Magnete

In what book did William Gilbert propose that Earth has a magnetic field?

isoclinic

Lines connecting points of equal inclination are _________ lines.

domain

Our understanding of how magnets work depends upon the _______ theory.

16

Quadrupling the current increases the strength of an electromagnet by a factor of _________.

declination

The amount by which a compass needle deviates from true north is the angle of _______?

magnetopause

The boundary of the magnetosphere is the ___________.

permeability

The extent to which a material can channel or absorb lines of magnetic flux is the material's _________.

current

The flow of charge from one place to another is _______.

electron spin

The most important cause of magnetism in magnetic materials is ________.

"south-seeking"

The north magnetic pole of the earth is a ________ pole.

field

The region surrounding a charged object in which other objects are attracted or repelled by electric force is an electric ________.

poles

The two points on a magnet where its magnetism is concentrated are the _________.

Van Allen

The two vast, doughnut-shaped belts of high-speed particles trapped in Earth's magnetic field are the ____ _______ radiation belts.

xerography

What is "dry writing" that uses electric charges to reproduce images on paper?

coulomb

What is the SI unit of charge called?

aurora

What is the display of shimmering light formed by high-speed particles spiraling into the upper atmosphere and crashing into air molecules?

deflecting

What is the force that changes the path of a charged particle moving through a magnetic field?

capacitor

What is the general term for a modern device used to store electric charge?

Curie point

What is the name for the temperature above which a ferromagnetic material has no domains?

grounding

What is the process of diverting unwanted electrical charge directly into the earth?

solar wind

What is the stream of charged particles that emanates from the sun called?

inclination

What phenomenon causes a vertical compass to point downward in the Northern Hemisphere?

electricity

What term refers to the interactions between electrons and other charged particles?

conduction

When a charged ball is touched to the knob of an electroscope, charge is transferred from the ball to the electroscope through ________.

law of magnetic poles

Which law states that like poles repel and unlike poles attract?

law of conservation of charge

Which law states that the total charge is the same before and after an interaction?

like charges repel

Why do the hairs of your head stand up straight and apart from each other if you are given a strong enough charge?

heat

________ is NOT a method of magnetization.

dipping needle

compass that swings vertically to reveal the angle at which lines of flux enter the earth

Leyden jar

early device used to store an electric charge

lodestone

form of magnetite that is a naturally occurring magnet

Van de Graff generator

most common electrostatic generator

lightning rod

protects buildings and other structures from lightning strikes

electroscope

simple device that detects small electric charges

electrostatics

the study of the nature, behavior, and uses of static electricity and related phenomena is _________.