Electric fields Flashcards
What is an electric field?
region of space in which any object with charge will experience a force
Where do electric fields exist?
around all objects with charge
State Coulomb’s law in symbols.
F = (Q1Q2)/4pi(permeability or free space)r^2
Give the electric field strength at any point in a field.
E = F/Q
Give the unit of electric field strength.
NC^-1
Give the field strength for a radial electric field at a distance r from a point charge Q.
E = Q/4pi(permeability of free space)r^2
How can a uniform electric field be produced?
applying a potential difference between two parallel metal plates
Give the properties of a uniform electric field.
field strength and direction are the same at every point
Give the formula for the magnitude of the electric field strength at any point in a uniform field.
E = V/d
What kind of trajectory will a charged particle entering a uniform field in a direction initially perpendicular to the field have?
parabolic trajectory
Define the absolute electric potential at a point in an electric field.
work done per unit charge to bring a small positive test charge from infinity to that point
Give the formula for the magnitude of the absolute electric potential at a point in a radial field caused by a charge.
V = Q/4pi(permeability of free space)r
What is electric potential difference?
difference between the electric potential at two points in an electric field
Give the formula for the work done in moving a charge between two points in an electric field.
(delta)W = Q(delta)V
What is an equipotential surface in an electric field?
surface where the electric potential is the same at all points
