Chapter 22 Electrostatics

Question 1

Electricity

Answer 1

General term for electrical phenomena, much like gravity has to do with gravitational phenomena, or sociology with social phenomena.

Question 2

Electrostatics

Answer 2

The study of electric charge at rest (not in motion, as in electric currents).

Question 3

Conservation of charge

Answer 3

Electric charge is neither created nor destroyed. The total charge before an interaction equals the total charge after.

Question 4

Coulomb’s Law

Answer 4

The relationship between electrical force, charge, and distance: F=k q1q2/d2

If the charges are alike in sign, the force is repulsive; if the charges are unlike, the force is attractive.

Question 5

Conductor

Answer 5

Any material having free charged particles that easily flow through it when an electric force acts on them.

Question 6

Coulomb

Answer 6

The SI unit of electrical charge. One coulomb (symbol C) is equal to the total charge of 6.25 x 10^18 electrons.

Question 7

Insulator

Answer 7

A material without free charged particles and through which charge does not easily flow.

Question 8

Semiconductor

Answer 8

A device composed of material not only with properties that fall between a conductor and an insulator but with resistance that changes abruptly when other conditions change, such as temperature, voltage, and electric of magnetic fields.

Question 9

Superconductor

Answer 9

A material that is a perfect conductor with zero resistance to the flow of electric charge.

Question 10

Charging by contact

Answer 10

Transfer of electric charge between objects by rubbing or simple touching.

Question 11

Charging by induction

Answer 11

Redistribution of electric charges in and on objects caused by electrical influence of a charged object close by but not in contact.

Question 12

Electrically polarized

Answer 12

Term applied to an atom or molecule in which the charges are aligned so that one side has a slight excess of positive charge and the other side a slight excess of negative charge.

Question 13

Electric field

Answer 13

Defined as force per unit charge, it can be considered to be an “aura” surrounding charged objects and is a storehouse of electric energy. About a charged point, the field decreases with distance according to the inverse-square law, like gravitational field. Between oppositely charged parallel plates, the electric field is uniform.

Question 14

Electric potential energy

Answer 14

The energy a charged object possesses by virtue of its location in an electric field.

Question 15

Electric potential

Answer 15

The electric potential energy per unit of charge, measured in volts, and often called voltage.

Question 16

Voltage

Answer 16

Electric potential energy/ amount of charge

Question 17

Capacitor

Answer 17

An electrical device - in its simplest form, a pair of parallel conducting plates separated by a small distance - that stores electric charge and energy.