click below
click below
Normal Size Small Size show me how
E-stim Terminology
terms associated with Electrical Stimulation
Question | Answer |
---|---|
electrical current | movement of flow of charged particles through a conductor in response to applied electrical field measured in amperes (A) |
charge | basic property of matter noted as Q measured in Coulombs (C) |
polarity | property of having 2 oppositely charged conductors |
voltage | electrical force capable of moving charged particles through a conductor between 2 regions measured in Volts (V) aka = Potential Difference |
resistance | Property of a conductor that resists, or is in opposition to the flow of charged particles. Resistance (R) is measured in Ohms Ώ |
Ohm's Law | V = I x R Voltage = Icurrent x Resistance |
impedance | The total frequency-dependent opposition to current flow. Impedance (Z) is measured in Ohms. For biological systems, Z describes the ratio of V to I more accurately than R because it is a frequency-dependent measure that includes capacitance and R. |
Direct Current | continuous unidirectional flow of charged particles (DC) |
Alternating Current | Alternating Current (AC) is a continuous bi-directional flow of charged particles AC has equal ion flow in each direction resulting in no net charge accumulation Wave length is one cycle ↑ frequency = ↓ cycle duration |
Pulsed Current | Discontinuous in a series of pulses which may be uni- or bidirectional [flow of charge is interrupted to create periods when no current flows] |
monophasic pulsed current | A series of unidirectional pulses. A net charge results. |
biphasic current | may be symmetrical or asymmetrical may be balanced or unbalanced |
Interferential Current | Waveform is produced by interference of two medium frequency sinusoidal AC of slightly different frequencies. Uses 2 channels, 4 electrodes, placed so AC currents intersect and interfere. |
intensity | aka = strength, power, or amplitude |