How is electric potential different from electric field strength?

Electric potential is the amount of electric potential energy per unit charge, while electric field strength is the force experienced by a unit positive charge.

Electric potential, also known as electric potential difference or voltage, is a measure of the work done per unit charge. It is a scalar quantity, meaning it only has magnitude and not direction. The unit of electric potential is the volt (V), which is equivalent to one joule per coulomb (J/C). Electric potential is caused by electric charges or changing magnetic fields. It is important to note that electric potential is a point property. It is defined at every point in space and is taken as zero at infinity. To understand this concept further, explore the principles of electric potential energy.

On the other hand, electric field strength, also known as electric field intensity, is a vector quantity that represents the amount of force experienced by a unit positive charge due to an electric field. It is measured in newtons per coulomb (N/C) or volts per metre (V/m). The direction of the electric field at a point is the direction of the force that a positive test charge would experience if placed at that point. The basics of electric fields can provide a foundation for understanding how forces are exerted in electric fields.

The relationship between electric field strength (E) and electric potential (V) can be expressed by the equation E = -dV/dr, where dV is the change in electric potential and dr is the change in position. This equation shows that the electric field strength is the negative gradient of the electric potential. For those interested in seeing this relationship graphically, reviewing equipotential surfaces may offer additional insights. Moreover, delving into calculations around electric fields can enhance your understanding of how to quantify and relate electric field strength to electric potential.

IB Physics Tutor Summary: Electric potential is about the energy a charge has due to its position, measured in volts, and doesn't have a direction. Electric field strength is the force a charge feels, measured in newtons per coulomb or volts per metre, and has a direction. The two are linked: the electric field is the rate at which electric potential changes with distance.