Formula Of Power In Terms Of Voltage And Current

In the above circuit we know we have a battery voltage of 18 volts and a lamp resistance of 3 ω.

Formula of power in terms of voltage and current. By multiplying the voltage in volts by the current in amps we arrive at an answer in watts let s apply this to a circuit example. The power formula is used to compute the power resistance voltage or current in any electrical circuit. Resistance if the electric power and the total resistance are known then the current can be determined by using the following formula. Electric power like mechanical power is the rate of doing work measured in watts and represented by the letter p the term wattage is used colloquially to mean electric power in watts the electric power in watts produced by an electric current i consisting of a charge of q coulombs every t seconds passing through an electric potential difference of v is.

This formula is derived from ohm s law. By ohm s law v ir and so there are additional forms of the electric power formula for resistors. The three basic principles for this tutorial can be explained using electrons or more specifically the charge they create. How much power does it use.

For any circuit element the power is equal to the voltage difference across the element multiplied by the current. Current is the rate at which charge is flowing. Voltage is the difference in charge between two points. Ampere a watt w ohm ω where p is the electric power.

Power is measured in units of watts w where a watt is equal to a joule per second 1 w 1 j s. How to use ohm s law to determine current. The standard metric unit of power is the watt. The movement of electrons.

They all operate using the same basic power source. An electric machine makes use of 300 j of energy to do work in 10s. We ve seen the formula for determining the power in an electric circuit.