Equipotential Lines

Equipotential Lines

Nhung Pham

Physics 1108 - General Physics Laboratory II

CRN 10089

August 30, 2012

Introduction

The purpose of this experiment was to plot the equipotential lines and construct the electric fields lines to determine the relationship between them.

Background

There is an electric field in any region where there is a force on an electric charge at rest. It is convenient to represent an electric field by the lines of force. The direction of the lines is the direction of the force on a positive electric charge in the field. The electric field intensity at any point is the force that would be exerted on a unit positive charge, +q, at that point (force per Coulomb). The electric field intensity is proportional to the number of electric lines of force per unit area.

The experiment contains the electric potential difference between two points in the field (VB – VA). The potential difference between points A and B is defined as the change in the potential energy of a charge q moved from A to B divided by the size of the charge.

ΔV = VB – VA = ΔPE /q (1)

An equipotential line is a set of points that all have the same potential. Since there is no change in potential, no work is required to move a charge on an equipotential line or surface. Therefore, there is no component of electric force along an equipotential line. Electric lines of force are always perpendicular to equipotential lines and the value is given.

VB - VA r∧ (2)

E = rB - rA

Procedure

1. Change the power supply’s voltage to 10 volts.

2. Attach electrode A and B to the power supply matching its color.

3. Attach the ends of the two electrodes with the alligator clip to the pins on the conducting paper....