Ohm's Law and Power/Energy Calculations

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Figures (5)

The electrons, the charge carriers in an electrical circuit, flow in the direction opposite that of the conventional electric current.

A proton conductor in a static electric field

A magnetic field is produced by an electric current in a solenoid.

Alternating electric current flows through the solenoid, producing a changing magnetic field. This field causes an electric current to flow in the wire loop by electromagnetic induction.

Key Points

Ohm's law states that in a well-behaved conductor (a so-called ohmic conductor), the electric current between two points is directly proportional to the voltage (the difference of electric potential) across the two points.
If voltage is forced to some value V, then that voltage V divided by measured current I will equal R.
The current I is adjusted to reestablish the balance position.
A resistance thermometer is included in a circuit that measures the thermometer's electric resistance.
The power of the compressor is 190 times larger than that of the pump in the previous example.
Energy and Temperature There is air in a flexible compartment at a pressure of 3 bar (43.51 psi).

Terms

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Sources & licensing(4)

Olivier Cleynen, Engineering Thermodynamics — thermodynamicsbook.com/ (Creative Commons Attribution-ShareAlike 4.0)
Howard DeVoe, Thermodynamics and Chemistry, 2nd edition — www2.chem.umd.edu/thermobook/ (Creative Commons Attribution 4.0)
Wikipedia contributors — en.wikipedia.org/wiki/Ohm's_law (Creative Commons Attribution-ShareAlike 4.0)
Wikipedia contributors — en.wikipedia.org/wiki/Electric_current (Creative Commons Attribution-ShareAlike 4.0)