Power Current Equation

The power taken by a circuit single or three phase is measured in watts w or kw.

Power current equation. If there is ac look also at the power factor pf cos φ and φ power factor angle phase angle between voltage and amperage. How much power does it use. This equation called ohm s law shows the. The resistance of an electrical component can be found by measuring the electric current flowing through it and the potential difference across it.

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. 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. Three phase power and current. The voltage v in volts v is equal to the current i in amps a times the resistance r in ohms ω.

Power is a scalar quantity. Learn the power formula. V v i a r ω. 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. In the international system of units the unit of power is the watt equal to one joule per second. How to use ohm s law to determine current. 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.

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. We ve seen the formula for determining the power in an electric circuit. Which can also be expressed as. In the above circuit we know we have a battery voltage of 18 volts and a lamp resistance of 3 ω.

Power voltage current resistance p v i r calculator. In physics power is the amount of energy transferred or converted per unit time. The standard metric unit of power is the watt. The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft.

The product of the voltage and current is the apparent power and measured in va or kva. In older works power is sometimes called activity. The relationship between kva and kw is the power factor pf. The power formula is used to compute the power resistance voltage or current in any electrical circuit.

Current flowing in the circuit i and resistance r. To get the result in watts work must be expressed in joules and time must.