Principle

Investigate what happens to the homogeneous electric field between two parallel rod electrodes, when the voltage, applied to the electrodes, is changed.

Benefits

• No electrolyte required
• Direct measurement of potential with high resistance voltmeter
• Measuring points can be transferred (pressed through) onto a sheet of white paper during measurement

Tasks

1. First of all, determine the distribution of equipotential lines within the electric field between the two electrodes for two different voltages.
2. Derive the concept of the electric field strength and observe how this quantity is affected by a change in voltage.

Learning objectives

With this experiment the students will observe how a homogeneous electric field between two rod electrodes changes when the voltage between the electrodes is altered.  The students will make conclusions based on the distribution of equipotential lines. They will draw the electric field pattern for two voltage configurations and elaborate the concept of the electric field strength.