Physics:lecture 7: Electricity And Magnetism

Front 1

Coulomb's Law

Back 1

F = k*q1*q2/r^2

Front 2

Lines of a positive force ________, and negative force ___________

Back 2

go outward, go inward

Front 3

Electric Field

Back 3

-A vector pointing in the direction of the field
-units of N/C

E = k*q1/r^2

Front 4

Force on a charge in an electric field:

Back 4

F = E*q

Front 5

The potential Energy (U) of a charge in an electric field:

Back 5

U = E*q*d

Front 6

Electric Potential Energy

Back 6

U = k*q1*q2/r

Front 7

Voltage

Back 7

-The potential for work by an electric field in moving any charge from one point to another
-Units = J/C

V = Ed
V = k*q1/r

Front 8

Equipotential Surfaces

Back 8

-A surface normal to the field that describes a set of points all w/ the same potential

Front 9

Electric Dipole

Back 9

Created by two opposite charges w/ equal magnitude

Front 10

Electric Dipole Moment

Back 10

A vector whose magnitude is the charge q on one of the charges times the distance d between the charges (points in opposite direction to E field, from neg to positive

Front 11

A dipole not perfectly aligned w/ an external electric field will have a potential energy of:

Back 11

U = -pEcos(theta)

Front 12

The electric field inside a uniformly charged conductor is _________

Back 12

zero

Front 13

Current

Back 13

-Given in amps, or C/s
-Flow in the direction of positive charge

Front 14

If an object is made from a homogeneous conductor, the resistance of the object when a voltage is applied uniformly to its ends =

Back 14

R = p*(L/A)

p = resistivity of material

Front 15

Voltage Formula

Back 15

V = iR

Front 16

Voltage is analogous to:

Back 16

gh

Front 17

Kirchoff's First Law

Back 17

The amount of current flowing into any node must be the same amount that flows out

Front 18

Node

Back 18

Any intersection of wires

Front 19

Kirchoff's Second Law

Back 19

The voltage around any path in a circuit must sum to zero

Front 20

Battery

Back 20

Adds energy to a circuit by increasing the voltage from one point to another (rated w/ EMF)

Front 21

Capacitor

Back 21

-Temporarily stores energy in a circuit (form of separated charge)

Front 22

Electric Field between parallel plate capacitors:

Back 22

E = (1/K)*(Q/A*eo)

eo = permittivity

k = 1/(4*pi*eo)

Front 23

Capacitance

Back 23

C = Q/V

Front 24

Formula for Parallel Plate Capacitor:

Back 24

C = K*(A*eo/d)

Front 25

Energy stored in any capacitor:

Back 25

U = (1/2)*Q*V

Front 26

Dielectric Constant (K)

Back 26

Refers to the substance between the plates of a capacitor (must be an insulator)

Front 27

Resistors in Series

Back 27

R(eff) = R1 + R2 + ...

Front 28

Resistors in Parallel

Back 28

1/R(eff) = 1/R1 + 1/R2 + ...

Front 29

Electrical Power

Back 29

P = i^2*R

Front 30

Power Dissipated

Back 30

The rate at which heat is dissipated in a resistor

Front 31

Max Current in AC circuit

Back 31

i(max) = sqrt(2*i(rms))

Front 32

rms

Back 32

root mean square. square root of the average of the squares.

Front 33

Capacitance

Back 33

C = Q/V

Front 34

Formula for Parallel Plate Capacitor:

Back 34

C = K*(A*eo/d)

Front 35

The lines of force in a magnetic field point from the ______ to the ________

Back 35

north to the south

Front 36

Energy stored in any capacitor:

Back 36

U = (1/2)*Q*V

Front 37

What creates a magnetic field?

Back 37

A changing electric field (i.e. from current)

Front 38

Dielectric Constant (K)

Back 38

Refers to the substance between the plates of a capacitor (must be an insulator)

Front 39

Magnetic Field for a long, straight wire:

Back 39

B = (uo*i)/(2*pi*r)

Front 40

Resistors in Series

Back 40

R(eff) = R1 + R2 + ...

Front 41

The force on a charge moving w/ velocity through a magnetic field:

Back 41

F = qvBsin(theta)

Front 42

Resistors in Parallel

Back 42

1/R(eff) = 1/R1 + 1/R2 + ...

Front 43

Electrical Power

Back 43

P = i^2*R

Front 44

Power Dissipated

Back 44

The rate at which heat is dissipated in a resistor

Front 45

Max Current in AC circuit

Back 45

i(max) = sqrt(2*i(rms))

Front 46

rms

Back 46

root mean square. square root of the average of the squares.

Front 47

The lines of force in a magnetic field point from the ______ to the ________

Back 47

north to the south

Front 48

What creates a magnetic field?

Back 48

A changing electric field (i.e. from current)

Front 49

Magnetic Field for a long, straight wire:

Back 49

B = (uo*i)/(2*pi*r)

Front 50

The force on a charge moving w/ velocity through a magnetic field:

Back 50

F = qvBsin(theta)

Front 51

T or F: The force due to a magnetic field does work

Back 51

False. It always acts the centripetal force and can be set equal to mv^2/r

Front 52

The force on a current carrying wire placed in a magnetic field:

Back 52

F = ilBsin(theta)