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52 Cards in this Set
 Front
 Back
Coulomb's Law

F = k*q1*q2/r^2


Lines of a positive force ________, and negative force ___________

go outward, go inward


Electric Field

A vector pointing in the direction of the field
units of N/C E = k*q1/r^2 

Force on a charge in an electric field:

F = E*q


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

U = E*q*d


Electric Potential Energy

U = k*q1*q2/r


Voltage

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 

Equipotential Surfaces

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


Electric Dipole

Created by two opposite charges w/ equal magnitude


Electric Dipole Moment

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


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

U = pEcos(theta)


The electric field inside a uniformly charged conductor is _________

zero


Current

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

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

R = p*(L/A)
p = resistivity of material 

Voltage Formula

V = iR


Voltage is analogous to:

gh


Kirchoff's First Law

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


Node

Any intersection of wires


Kirchoff's Second Law

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


Battery

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


Capacitor

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


Electric Field between parallel plate capacitors:

E = (1/K)*(Q/A*eo)
eo = permittivity k = 1/(4*pi*eo) 

Capacitance

C = Q/V


Formula for Parallel Plate Capacitor:

C = K*(A*eo/d)


Energy stored in any capacitor:

U = (1/2)*Q*V


Dielectric Constant (K)

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


Resistors in Series

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


Resistors in Parallel

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


Electrical Power

P = i^2*R


Power Dissipated

The rate at which heat is dissipated in a resistor


Max Current in AC circuit

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


rms

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


Capacitance

C = Q/V


Formula for Parallel Plate Capacitor:

C = K*(A*eo/d)


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

north to the south


Energy stored in any capacitor:

U = (1/2)*Q*V


What creates a magnetic field?

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


Dielectric Constant (K)

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


Magnetic Field for a long, straight wire:

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


Resistors in Series

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


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

F = qvBsin(theta)


Resistors in Parallel

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


Electrical Power

P = i^2*R


Power Dissipated

The rate at which heat is dissipated in a resistor


Max Current in AC circuit

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


rms

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


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

north to the south


What creates a magnetic field?

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


Magnetic Field for a long, straight wire:

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


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

F = qvBsin(theta)


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

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


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

F = ilBsin(theta)
