Ch. 5: Electrostatics and Magnetism

Question 1

Coulomb

Answer 1

SI unit of charge

Question 2

Conductors

Answer 2

Allow the free and uniform passage of electrons when charged

Question 3

Insulators

Answer 3

Resist the movement of charge and will have localized areas of charge that do not distribute over the surface of the material

Question 4

Coulomb’s Law

Answer 4

Gives the magnitude of the electrostatic force vector between two charges. The force vector always points along the line connecting the centers of the two charges

Question 5

Electric Field

Answer 5

Every charge generates an electric field, which can exert forces on other charges. Ratio of the force that is exerted on a test charge to the magnitude of that charge

Question 6

Field Lines

Answer 6

Electric field vectors can be represented as field lines that radiate outward from positive source charges and radiate inward to negative source charges. Positive test charges will move in the direction opposite of the field lines.

Question 7

Electric Potential Energy

Answer 7

Amt of work required to bring the test charge from infinitely far away to a given position in the vicinity of a source charge. Increases when 2 like charges move toward each other or when two opposite charges move further apart. Decrease when 2 opposite charges move toward each other or when two like charges move further apart

Question 8

Electric Potential

Answer 8

Electric potential energy per unit charge. Diff points in the space of an electric field surrounding a source charge will have diff electric potential values.

Question 9

Voltage

Answer 9

Potential difference is the change in electric potential that accompanies the movement of a test charge from one position to another. Path independent and depends only on the initial and final positions of the test charge.

Question 10

Volts

Answer 10

Units for electric potential and voltage

Question 11

Test charge movement

Answer 11

Test charges will move spontaneously in whichever direction results in a decrease in their electric potential energy. Positive test charges will move spontaneously from high potential to low potential. Negative test charges will move spontaneously from low potential to high potential.

Question 12

Equipotential lines

Answer 12

Designate the set of points around a source charge or multiple source charges that have the same electric potential. Always perpendicular to electric field lines. Work will be done when a charge is moved from one equipotential line to another; the work is independent of the pathway taken between the lines. No work is done when a charge moves from a point on an equipotential line to another point on the same equipotential line

Question 13

Electric dipole

Answer 13

Two charges of opposite sign separated by a fixed distance, d, generate an electric dipole. In an external electric field, an electric dipole will experience a net torque until it is aligned w the electric field vector. An electric field will not induce any translational motion in the dipole regardless of its orientation with respect to the electric field vector.

Question 14

Magnetic fields

Answer 14

Created by magnets and moving charges

Question 15

SI unit for magnetic field

Answer 15

Tesla (T = 10,000 gauss)

Question 16

Diamagnetic materials

Answer 16

Posses no unpaired electrons and are slightly repelled by a magnet

Question 17

Paramagnetic materials

Answer 17

Possess some unpaired electrons and become weakly magnetic in an external magnetic field.

Question 18

Ferromagnetic materials

Answer 18

Possess some unpaired electrons and become strongly magnetic in an external magnetic field

Question 19

Magnets

Answer 19

Have a north and south pole– field lines point from north to south pole

Question 20

Current carrying wires

Answer 20

Create magnetic fields that are concentric circles surrounding the wire

Question 21

External magnetic fields

Answer 21

exert forces on charges moving in any direction except parallel or antiparallel.

Question 22

Point charges

Answer 22

May undergo uniform circular motion in a uniform magnetic field wherein the centripetal force is the magnetic force acting on the point charge.

Question 23

Direction of magnetic force on a moving charge or current-carrying wire

Answer 23

Determined using right-hand rule

Question 24

Lorentz force

Answer 24

Sum of the electrostatic and magnetic forces acting on a body