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In practice, the internal resistance of a battery is dependent on its size, state of charge, chemical properties, age, temperature, and the discharge current. It has an electronic component due to the resistivity of the component materials and an ionic component due to electrochemical factors such as electrolyte conductivity , ion mobility ...
Car radios used electromechanical vibrators to transform the 6 V battery supply to a suitable plate voltage for the vacuum tubes. [7] 1959 Transistor oscillation and rectifying converter power supply system U.S. patent 3,040,271 is filed by Joseph E. Murphy and Francis J. Starzec, from General Motors Company [8] 1960s
In this type the resistance varies with the applied voltage or current. Negative resistance vs positive resistance: If the I–V curve has a positive slope (increasing to the right) throughout, it represents a positive resistance. An I–V curve that is nonmonotonic (having peaks and valleys) represents a device which has negative resistance.
Internal resistance is a concept that helps model the electrical consequences of the complex chemical reactions inside a battery. It is impossible to directly measure the internal resistance of a battery, but it can be calculated from current and voltage data measured from a circuit.
Simplified model for powering a load with resistance R L by a source with voltage V S and resistance R S.. The theorem was originally misunderstood (notably by Joule [4]) to imply that a system consisting of an electric motor driven by a battery could not be more than 50% efficient, since the power dissipated as heat in the battery would always be equal to the power delivered to the motor when ...
Voltage drops in the internal resistance of the source, across conductors, across contacts, and across connectors are undesirable because some of the energy supplied is dissipated. The voltage drop across the load is proportional to the power available to be converted in that load to some other useful form of energy.
In the case of transistor current sources, impedances of a few megohms (at low frequencies) are typical. Because power is current squared times resistance, as a load resistance connected to a current source approaches zero (a short circuit), the current and thus power both approach zero. Ideal current sources don't exist.
The current through an ideal voltage source is completely determined by the external circuit. When connected to an open circuit, there is zero current and thus zero power. When connected to a load resistance, the current through the source approaches infinity as the load resistance approaches zero (a short circuit). Thus, an ideal voltage ...