Electric Field Flashcards
What is Coulomb’s Law?
The magnitude of the electric force between 2 point charges is directly proportional to the product of the charges and inversely proportional to the square of their separation.
(basically the same as NLG)
What is the formula for Coulomb’s Law?
F = Q1Q2/4πε0r^2
Comparison between Coulomb’s Law and NLG?
same:
1. r is the centre-to-centre separation of the objects
2. Due to N3L, the forces that masses or charges exert on each other are equal in magnitude and opposite in directions.
different:
1. gravitational force is always attractive while electric force can be both repulsive and attractive.
^ can ask qns regarding the field lines too (i.e. which field lines can these be?)
Definition of electric field
A region of space where a charge experience an electric force
Definition of electric field strength
It is defined as the electric force per unit POSITIVE charge placed at that point. (literally just the equation)
what is the formula for electric field strength?
E = F/q
What is the formula for electric field strength near a point charge?
E = 1/4πε0 x Q/r^2 (literally the same as grav field, 1 charge over square of separation)
What is the formula for the electric field strength between 2 charged parallel plates?
E = ΔV/d
!! important yes !!
What is the definition of Electric Potential Energy?
it is defined as the work done against the electric force by an external agent in bringing the point charge from infinity to that point without any net change in KE. (roughly the same as GPE)
!! force by external agent is always in the opposite direction of the electric force !!
What is the definition of Electric Potential?
It is defined as the work done against the electric force per unit positive charge by an external agent in bringing a small test charge from infinity to that point without any net change in KE.
What is the formula for Electric Potential Energy?
U = qV
What are some of the relationships between Electric Force, Electric Field Strength, Electric Potential Energy and Electric Potential?
Electric Force = - dU/dx
Electric Field Strength = -dV/dx
What is the work done in bringing a point charge near another point charge?
W = U = 1/4πε0 x qQ/R
What is the electric potential in the field of a point charge?
V = 1/4πε0 x Q/r
