Power Current Resistance

Deriving power and resistance formula will concrete the understanding of the concept.

Power current resistance. 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. When power is high resistance will be low. Learn the power formula. In this calculator table you may enter two of the four factors in ohm s law.

Power power p is a measure of the rate at which energy is delivered or used by a circuit element. Voltage sources deliver power while resistors use power by dissipating it as heat. This brings us back to georg ohm. The power p in watts w is equal to the voltage v in volts v times the current i in amps a.

Power voltage current resistance p v i r calculator. 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. But we have designed this one especially for dc circuits as well as work for single phase ac circuits without power factor. 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.

Power and resistance formula. The circuit with the higher resistance will allow less charge to flow meaning the circuit with higher resistance has less current flowing through it. How to use ohm s law to determine current. The amount of current in a circuit depends on the amount of voltage and the amount of resistance in the circuit to oppose current flow.

They are power p or w measured in watts voltage v or e measured in volts current or amperage i measured in amps amperes and resistance r measured in ohms. V v i a r ω. The electrical relationships between resistance r current i power p and voltage e is defined by ohm s law. Power within an electrical circuit is only present when both voltage and current are present.

The voltage v in volts v is equal to the current i in amps a times the resistance r in ohms ω. Ohm defines the unit of resistance of 1 ohm as the resistance between two points in a conductor where the application of 1 volt will push 1 ampere or 6 241 10 18 electrons. Electric power p is the measure of the electric current i with q coulombs of charge passing through a potential difference of v volts in. One ohm is defined as the resistance which allows the current of one ampere under a potential difference of 1 volt.

When power is low the resistance will be high. The current is equal to the electromotive force of the source divided by the total circuit resistance. In the above circuit we know we have a battery voltage of 18 volts and a lamp resistance of 3 ω.