electric field & electric potential Flashcards
what is an electric field?
A field is a physical quantity that has a value for each point in space
what does q1 do in Coulomb’s law in regards to the electric field?
q1 - produces an electric field everywhere in space
what does q2 do in Coulomb’s law in regards to the electric field?
q2 - experiences a force due to this electric field
what is a source charge?
Charges that produce a force on the test charge
what is a test charge?
We are interested in the force on the test charge
how to work out the test charge?
using coulombs law
is the force on a charge at P and charge related?
(force on a charge at P) proportional to the (charge)
what is electric field?
(force on a charge at P) = (charge) × (some vector)
what is the some vector in the equation of …?
“some vector” is called the electric field at the point P and is given the symbol E
what is the symbol for the electric field at point P?
capital E
what is the equation for the electric field at point P?
F = q × E or E = F/q
what are the units for the electric field at point P?
unit for electric field is newtons per coulomb (NC−1)
what equation is really similar to the Colombs law equation?
electric field due to a point charge equation
What’s the difference between the Colombs law equation and the electric field due to a point charge equation?
there is one less Q (charge) and the start has E (electric force) instead of F (force)
what happens if the source charge is positive?
source charge is positive the electric field points away
from the source charge.
what happens if the source charge is negative?
If the source charge is negative the electric field points
towards the source.
what happens if there is more than one source charge?
If there is more than one source charge, then the
superposition principle says you calculate the electric fields
due to each of the source charges individually and then sum
the result.
