Week 3: Intro to Gauss's law Flashcards
Gauss’s Law Equation
EAcos(theta)=q/(e04pi)
Epsilon Naught (e0) Value
e0 = 8.85X10^-12 F(fardas)/m
𝜎
Q/(𝝅r^2)
Electric Flux is proportional to?
Sources Inside
conductor
object with properties that allow charges to move about freely within it
dipole
two equal and opposite charges that are fixed close to each other
ρ (rho)
charge/volume
Flux
How a vector field goes through an electric surface / how many field lines go through an electric field
how is D and electric field related inside a charged object
As D increases, electric field increases
What is q enc
the enclosed charge
Surface area of a sphere
4πR^2
Q for a sphere
p(4/3)πR^3
D
Distance to the point of interest in a sphere
When D and R are equal
The electric field of charged sphere is at its max
E(4(pi)D^2)=
Q/ε0 for spherical distributions
What is P?
P = charge/volume
What is Enet?
Enet is the total electric field
When an electric flux = 0
The electric flux will be zero when the area vector is perpendicular to the direction of the electric field
n̂
a unit vector perpendicular to the plane formed by the two vectors
Relationship D and E inside a charged sphere
Linear - as the distance from the center gets bigger, the charge (E) increases
k value
9X10^9
Equation for E when the POI is within the charged sphere
E = (pd/3Eo)
What does D represent
The radius of sphere enclosing the charge
What is P.O.I
point of interest
What is the Gaussian surface also known as?
The closed/imaginary surface
What shape does the electric field take on?
Whatever the shape of the charged surface is.
Calculating the electric field outside of a solid sphere
E=kQ/D^2 or E=Q/(4pi eO D^2)
In what direction do the electric field arrows face of a positive charge?
Outwards from charge
In what direction do the electic field arrows face from a negative charge?
Towards the charge
R
The radius of the real surface
As D increases what does E do inside the charged object?
E increases
Formula for an electric field involving a disk
E = (k𝜎2pi)*(1-(D/(sqrt(D^2+R^2)))
Formula for an electric field involving a ring
E = (k2piRλD)/((R^2+D^2)^3/2)
