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Ohms' Law Calculator
Ohm's Law defines the relationship between voltage (V), current (I), power (P) and resistance (R) in electrical circuits. It was discovered in 1827 by Georg Ohm (1789 – 1854), a German mathematician and physicist who, as a high school teacher, decided to study Alessandro Volta's new invention: the electromechanical cell (the precursor of the battery).
The relationships between the four important parameters of circuits are as follows:
  1. Voltage (V, in volts) calculations:
  2. Current (I, in amps) calculations:
  3. Power (P, in watts) calculations:
  4. Resistance (R, in Ω) calculations:
To use this calculator, enter a value for any two of the following: voltage, current, resistance, and power.
Voltage:
Current:
Resistance:
Power:
  
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Engineering Calculator Disclaimer
GlobalSpec, Inc. engineering calculators are free for individuals to use via this site under the terms and conditions set out under the Terms of Use of this web site and supplemented by this Engineering Calculator Disclaimer. These calculators are intended solely for general information and educational purposes, and are provided to help decrease the learning curve for those inexperienced in the engineering field and to give more experienced users additional reference tools.
The engineering calculators provided are not intended in any way as engineering advice or services, or as a solicitation for any engineering product or service. Any results from use of these calculators may not be applicable or accurate with regard to the individual circumstances, cannot be relied upon for anything, including, without limitation, engineering designs or decisions, and should not be the basis for any action or inaction on your part. Read Entire Disclaimer
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