Chapters 22-24

Question 1

A material which readily transmits current is called a(n)…..

Answer 1

conductor

Pg. 328

Question 2

A production of charge by the influence of another charged body at a distance is called …..

Answer 2

induction

Pg. 330

Question 3

Magnetizing a material by bringing it into the presence of an existing magnet is called magnetization by …..

Answer 3

induction

Pg. 342

Question 4

The law of magnetic force was formulated by …..

Answer 4

Coulomb

Pg. 343

Question 5

Materials which are strongly attracted by magnets are said to be ……

Answer 5

ferromagnetic

Pg. 347

Question 6

Magnetic induction can be measured in any of the following units except …..

Answer 6

Magnetic induction can be measured in:
T(tesla) =N/A•m
T= Wb/m^2

Pg. 352, 355

Question 7

The generation of current in a conductor moving in a magnetic field is called …..

Answer 7

electromagnetic induction

Pg. 359

Question 8

Which of the following did Faraday not demonstrate by thrusting a bar magnet into a coil?

Answer 8

Faraday did demonstrate:
1. The mere presence of a magnetic field is not enough to induce current within a coil.
2. Current is induced within a coil by relative motion between the coil and a magnetic field.
3. The speed of the relative motion between a coil and a magnetic field determines how much current is produced.
4. The current induced by a magnetic field depends on the strength of the field.
5. The current varies directly with the number of turns in the coil.
Pg. 362

Question 9

A device that produces current by electromagnetic induction is called a(n) …..

Answer 9

electromagnetic generator

Pg. 366

Question 10

Completion

A(n) ….. is used for testing the charge of an object.

Answer 10

electroscope

Pg. 331

Question 11

The only available charge carriers in a solid material are …..

Answer 11

electrons

Pg. 328

Question 12

Any piece of magnetized rock is known as a(n) …..

Answer 12

lodestone

Pg. 341

Question 13

When neighboring atomic dipoles orient themselves in the same direction and spread this orientation to other atoms a(n) ….. is formed.

Answer 13

domain

Pg. 346

Question 14

When current flows through a liquid, ….. are the carriers of electrical charge.

Answer 14

atoms

Pg. 328

Question 15

The SI unit of magnetic induction is the …..

Answer 15

Tesla

Pg. 344

Question 16

A positive electrode of an electrochemical cell is called a(n) …..

Answer 16

cathode

Pg. 373

Question 17

A device in which two conductors come together at junctions but are maintained at different temperatures is called a(n) …..

Answer 17

thermocouple

Pg. 375

Question 18

A ….. crystal produces a potential difference between its opposite faces when a mechanical stress is applied to it.

Answer 18

piezoelectric

Pg. 376

Question 19

….. law states that induced current is directed so as to create a magnetic field that opposes the motion causing the current.

Answer 19

Lenz’s

Pg. 365

Question 20

True/False

The total charge on any insulated object or insulated system of connected objects is (conserved).

Answer 20

True

Pg. 333

Question 21

Lines of (flux) always originate in a positively charged body and terminate in a negatively charged body.

Answer 21

force

Pg. 334

Question 22

All charge is confined to the (surface) of a conductor.

Answer 22

True

Pg. 338

Question 23

Any charge on a (cubical) conductor is distributed uniformly over the exterior surface.

Answer 23

spherical

Pg. 338

Question 24

The material of a (permanent) magnet is easily magnetized and easily demagnetized.

Answer 24

temporary

Pg. 343

Question 25

(Decreasing) the temperature of a magnet destroys its ability to retain its magnetization.

Answer 25

Increasing | Pg. 342

Question 26

The needle of Oersted's compass experiment moved when current was turned on or off in a wire running (parallel) to the original direction of the needle.

Answer 26

True | Pg. 348

Question 27

One difference between AC and DC generators is that an (AC) generator has a commutator.

Answer 27

DC | Pg. 368

Question 28

Electrochemical cells connected together constitute a (battery).

Answer 28

True | Pg. 374

Question 29

The voltage of cells in series is the (sum) of their separate voltages.

Answer 29

True | Pg. 374

Question 30

Matching ``` coulomb current Electric field strength Electric potential Electric potential energy Voltage ``` The force exerted on a charge Amount of work done in transporting total charge from the ground to a specified point Amount of work done by an external force to move a unit of positive charge from point A to point B on a conductor The total charge of 6.242 X 10 ^18 electrons

Answer 30

Matching ``` coulomb current Electric field strength Electric potential Electric potential energy Voltage ``` The force exerted on a charge = electric field strength Amount of work done in transporting total charge from the ground to a specified point = electric potential energy Amount of work done by an external force to move a unit of positive charge from point A to point B on a conductor = electric potential difference The total charge of 6.242 X 10 ^18 electrons = coulombs

Question 31

Equations Calculates the magnetic force on a straight conductor

Answer 31

``` F= BI(L) Magnetic force B= magnetic induction I= carrying current I Lowercase L for length ``` Pg. 352 Pg. 352

Question 32

Equation Calculates the magnetic force on a moving charge

Answer 32

``` F= qvB Magnetic force q= charge's magnitude B = magnetic induction Pg. 354 ```

Question 33

Short answer Describe how an insulated, grounded metal sphere can be given a lasting positive charge by induction

Answer 33

An insulated, grounded metal sphere can be given a lasting positive charge through induction by holding a negatively charged rubber rod near the metal sphere; and the sphere will acquire a positive charge to counteract the negative charged rod near it. Once a positive charge is gained by the sphere the charge will stay even after the connection to the ground is broken and the rod is removed from its vicinity. Pg. 330

Question 34

Describe how you can find the direction of magnetic force on moving charges by using the left-hand three-finger rule

Answer 34

With your left hand, point your thumb in the direction of negative current; your extended, straight index finger points in the direction of magnetic induction, and your bent middle finger shows the direction of magnetic force. Pg. 353

Question 35

Name two ways we can increase the frequency of the current produced by an AC generator.

Answer 35

Two ways to increase the frequency of the current produced by an AC generator is by rotating the armature faster or by increasing the number of magnetic poles surrounding the armature. Pg. 368