Unit 4: Electric Fields

Electric Fields have many similarities with gravitational fields (see table later). The main difference is that while gravitational fields can only produce attractive forces, electric fields can create both attractive and repulsive forces. We can calculate the magnitude of these forces using Coulomb’s Law

•  F= 1/4πε₀ x Q₁Q₂/r²

•  F= q₁q₂/ 4πε₀

As we get further away from the point charge, the field (and hence the force on another charge) gets weaker. The field is spherical, so the field decreases by a factor of 1/r²

Equipotentials are regions where the electric potential is the same. 

In a uniform field (e.g. one created by two parallel plates), equally-spaced lines of equipotential are formed.

In a spherical field formed by point charges (e.g. particles such as single electrons), the field points in the direction of the force that the other particle experiences from the point charge (ie. a positively-charged particle will experience a field…