Current transformer current transformers" are also used (usually with an oscilloscope) to measure waveforms of high frequency or pulsed currents within pulsed power systems. Unlike CTs used for power circuitry, wideband CTs are rated in output volts per ampere of primary current. If the burden resistance is much less than inductive impedance of the secondary winding at the measurement frequency then the current in the secondary tracks the primary current and the transformer provides a current output that is proportional to the measured current. On the other hand, if that condition is not true, then the transformer is inductive and gives a
History of electromagnetic theory potential difference. He used a galvanometer to measure current, and knew that the voltage between the thermocouple terminals was proportional to the junction temperature. He then added test wires of varying length, diameter, and material to complete the circuit. He found that his data could be modeled through a simple equation with variable composed of the reading from a galvanometer, the length of the test conductor, thermocouple junction temperature, and a constant of the entire setup. From this, Ohm determined his law of proportionality and published his results. In 1827, he announced the now famous law that bears his name,