Power Voltage Current Equation

But we have designed this one especially for dc circuits as well as work for single phase ac circuits without power factor.

Power voltage current equation. In the above circuit we know we have a battery voltage of 18 volts and a lamp resistance of 3 ω. Common electrical units used in formulas and equations are. 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. 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.

Ohm unit of resistance one ohm is the resistance offered to the passage of one ampere when impelled by one volt. The voltage v in volts v is equal to the current i in amps a times the resistance r in ohms ω. Learn the power formula. For example in an open circuit condition voltage is present but there is no current flow i 0 zero therefore v 0 is 0 so the power dissipated within the circuit must also be 0 likewise if we have a short circuit condition current flow is present but there is no voltage v 0 therefore 0 i 0.

To get the result in watts work must be expressed in joules and time must. Power voltage current resistance p v i r calculator. How to use ohm s law to determine current. V v i a r 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. Introducing the constant of proportionality the resistance one arrives at the usual mathematical equation that describes this relationship. Voltage is represented in equations and schematics by the letter v. Where i is the current through the conductor in units of amperes v is the voltage measured across the conductor in.

Ampere units of current one ampere is the current which one volt can send. We ve seen the formula for determining the power in an electric circuit. 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. Volt unit of electrical potential or motive force potential is required to send one ampere of current through one ohm of resistance.

When describing voltage current and resistance a common analogy is a water tank. In this analogy charge is represented by the water amount voltage is represented by the water pressure and current is represented by the water flow. So for this analogy remember. 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.

Power formula 1 electrical power equation. Power within an electrical circuit is only present when both voltage and current are present.