Current Power Voltage Equation

By ohm s law v ir and so there are additional forms of the electric power formula for resistors.

Current power voltage equation. Power formula 1 electrical power equation. We ve seen the formula for determining the power in an electric circuit. 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. But we have designed this one especially for dc circuits as well as work for single phase ac circuits without power factor.

How to use ohm s law to determine current. Power p i v r i 2 v 2 r where power p is in watts voltage v is in volts and current i is in amperes dc. The watts equation for an electrical circuit takes into account the voltage across the circuit v measured in volts and the current i measured in amps passing through it in mechanics the definition of power is the rate of doing work w it s defined as w t where t is the time it takes for the work to be completed. To get the result in watts work must be expressed in joules and time must.

If there is ac look also at the power factor pf cos φ and φ power factor angle phase angle between voltage and amperage. Ohm s law states that the current through a conductor between two points is directly proportional to the voltage across the two points. Where i is the current through the conductor in units of amperes v is the voltage measured across the conductor in. This calculator is based on simple ohm s law as we have already shared ohm s law p i v r calculator in which you can also calculate three phase current.

For any circuit element the power is equal to the voltage difference across the element multiplied by the current. Introducing the constant of proportionality the resistance one arrives at the usual mathematical equation that describes this relationship. In the above circuit we know we have a battery voltage of 18 volts and a lamp resistance of 3 ω. 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.