This "'retarding potential method "'is one of the simplest and oldest methods of measuring work functions, and is advantageous since the measured material ( collector ) is not required to survive high temperatures.
2.
If " q e " is the charge on the electron and V _ 0 is the stopping potential, then the work done by the retarding potential in stopping the electron is q _ eV _ 0, so we have
3.
Experiment instrumentation included an RF impedance probe, an ion current monitor, a retarding potential probe, a two-element and a three-element electron temperature probe, an electron current monitor, a photomultiplier-type and a microphone-type micrometeorite detector, an electric field meter, a solar horizon sensor, and thermistor temperature probes.
मोबाइल