Search results
Results From The WOW.Com Content Network
One of the functions of many types of multimeters is the measurement of resistance in ohms.. The ohm is defined as an electrical resistance between two points of a conductor when a constant potential difference of one volt (V), applied to these points, produces in the conductor a current of one ampere (A), the conductor not being the seat of any electromotive force.
Power is the rate at which energy is generated or consumed and hence is measured in units (e.g. watts) that represent energy per unit time. For example, when a light bulb with a power rating of 100 W is turned on for one hour, the energy used is 100 watt hours (W·h), 0.1 kilowatt hour, or 360 kJ .
The more regular the lattice is, the less disturbance happens and thus the less resistance. The amount of resistance is thus mainly caused by two factors. First, it is caused by the temperature and thus amount of vibration of the crystal lattice. Higher temperatures cause bigger vibrations, which act as irregularities in the lattice.
The resistance is a consequence of the motion of charge through a conductor: in metals, for example, resistance is primarily due to collisions between electrons and ions. Ohm's law is a basic law of circuit theory , stating that the current passing through a resistance is directly proportional to the potential difference across it.
The work per unit of charge is defined by moving a negligible test charge between two points, and is expressed as the difference in electric potential at those points. The work can be done, for example, by electrochemical devices ( electrochemical cells ) or different metals junctions [ clarification needed ] generating an electromotive force .
Electric power is the rate of transfer of electrical energy within a circuit.Its SI unit is the watt, the general unit of power, defined as one joule per second.Standard prefixes apply to watts as with other SI units: thousands, millions and billions of watts are called kilowatts, megawatts and gigawatts respectively.
Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into useful forms of power – mainly electricity, dynamic tidal power, tidal lagoons, tidal barrages Wave power is the transport of energy by ocean surface waves , and the capture of that energy to do useful work — for example, electricity ...
Volta had determined that the most effective pair of dissimilar metals to produce electricity was zinc and silver. In 1861, Latimer Clark and Sir Charles Bright coined the name "volt" for the unit of resistance. [11] By 1873, the British Association for the Advancement of Science had defined the volt, ohm, and farad. [12]