Electricity and Magnetism Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

unit of charge

A

coulombs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

current run….

A

in the opposite direction of electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Universal Law of Conservation of Charge

A

every time a negative charge in created, a positive charge is created, and vice versa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Coulomb’s Law

A

F = Kq_1q_2/r^2

magnitude of force of repulsion or attraction between 2 charged objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

both gravitational and electric forces change inversely with…

A

the square of the distance between the centers of mass or charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

field

A

some type of distortion or condition in space that creates a force on a charge, or mass if gravitational field, or magnet if magnetic field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

lines of force

A

represent a field, point in direction of field (positive to negative for electric fields), closer lines = stronger field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

field lines point ____ for electric fields

A

positive to negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

electric field from point charge, E =

A

E = kq_1/r^2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

force on charge in electric field=

A

F = Eq

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

potential energy of charge in E field=

A

force x displacement

U = Eqd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

electric potential energy from point charge =

A

U = kq_1q_2/r

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

voltage

A

potential for work by an electric field in moving any charge from one point to another
V = Ed
units: J/C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

voltage due to point charge

A

V = kq_1/r

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

equipotential surfaces

A

all points on surface are same voltage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

electric dipole

A

created by two opposite charges with equal magnitude

17
Q

resistivity

A

quantitative measure of substance’s resistance to flow of charge

18
Q

resistance (R)

A

quantitative measure of an object of a particular shape and size to resist the flow of charge, in ohms

19
Q

Ohm’s Law

A

V = iR

20
Q

Kirchoff’s rule

A

amount of current flowing into any node must be the same amount that flows out
voltage around any path in a circuit must sum to zero

21
Q

EMF

A

the voltage on a battery

22
Q

capacitor

A

to temporarily store energy in a circuit in the from of separated charge

23
Q

parallel plate capacitor

A

two plates fade from conductive material separated by a very small distance, one plate positive other plate same amount of negative charge

24
Q

capacitance

A

ability to store charge per unit voltage, something with high capacity can store a lot of charge at low voltage
C = Q/V

25
Q

energy stored by any shape capacitor

A
U = 1/2QV
U = 1/2CV^2
U = 1/2Q^2/C
26
Q

dielectric constant, k

A

the substance between the plates of a capacitor

must be an insulator, acts to resist the creation of an electric field and allows the capacitor to store more charge

27
Q

resistors in series

A

Reff = R1 + R2 + R3…

28
Q

resistors in parallel

A

1/Reff = 1/R1 + 1/R2…

29
Q

capacitors in parallel

A

Ceff = C1 + C2 +….

30
Q

capactiors in serioes

A

1/Ceff = 1/C1 + 1/C2.

31
Q

electrical power

A
P = iV
P = i^2*R
P = V^2/R
32
Q

direct vs. alternating current

A
direct = net movement  of e-s is in one direction around circuit 
alternating = created by oscillating e-s back and forth in simple harmonic motion
33
Q

voltage and current for ac curernts

A

root mean square
Vrms = sqrt(2)/2Vmax
Irms = sqrt(2)/2
I max

34
Q

magnetic field strength measured in….

A

units of tesla, T

35
Q

static electric field produces ____ force on a magnet, static magnetic field produces ____ force on an electric charge

A

NO

36
Q

changing an electric field induces a _____, and changing a magnetic field induces an _____

A

magnetic field, electric field

37
Q

force on a charge moving through a magnetic field

A
F = qvBsin(theta) 
theta = angle between magnetic field and velocity of the charge
38
Q

a charged particle moving through a magnetic field….

A

will be forced into a curved path