Appendix; Ohm's Law Conversions - VWR 250V Manual De Instrucciones

APPENDIX

Ohm's Law Conversions

Electrophoresis is the migration of a charged particle under the influence of an electrical field.
The power supply output parameters voltage, current, and power are related by the following
two equations:
Voltage (V) = Current (I) x Resistance (R); (V=IR)
Power (W) = Current (I) x Voltage (V); (W=IV)
Resistance
Resistance of the assembled electrophoresis cell is dependent on the conductivity of the gel
buffer, the thickness of the gel, and the number of gels being run. Although the resistance is
determined by the gel system, the resistance can vary over the course of an electrophoretic
separation.
Voltage
The velocity with which an ion moves in an electric field will vary in proportion to the field
strength (volts per unit distance). The higher the voltage the faster an ion will move.
Current
Current is a function of the number of ions passing a given cross-section of the circuit at a
given time. For a given gel/buffer system, at a given temperature, current will vary in proportion
to the field strength (voltage) and/or cross-sectional area (number and/or thickness of the
gels).
Power
The power in Watts, or the rate of heat generated by the system, is directly proportional to
voltage and current (W=IV).
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Revision 1.0