Ohm’s Law Calculator

Ohm’s Law Calculator

Resistance (R):
Current (I):
Voltage (V):
Power (P):
   
There are two types of ohm's calculator depending on the calculations you intend to perform. The ohm's Law Calculator performs a variety of calculations relating to current, voltage, power and resistance. It has four text fields with a range of options on the second column.

You can choose the resistance (R) depending on ohms (Ω), Kiloohms (kΩ), and mega ohms (MΩ). The Current (I) can either be in amps (A), microamps (µA), milliamps (mA), Kilo amps (kA) or mega amps (MA). The voltage (V) can be calculated in volts (V), microvolts (µV), millivolts (mV), kilovolts (kV) or megavolts (MV). The last text field will require you to enter the Power (P) which can either be in Watts (w), microwatts (µW), milliwatts (mW), kilowatts (kW) or megawatts (MW).

For example,
if you enter the Resistance as 34 ohms and the current to be 50 amps, the voltage and power will be calculated automatically as 1700 Volts and 85000 watts respectively. This calculator is flexible and can be adjusted depending on the specific units you need to be converted.

AC Ohm's Law calculator

Impedance (Z): °  = 
Current (I): °    
Voltage (V): °    
Power (S): °  = 
       
It has some slight difference when compared to the first ohms law calculator. It requires you to enter two values of magnitude and phase angle which calculates the other values automatically. The text fields are arranged in a similar pattern only that it begins with the Impedance (Z), followed by Current (I), Voltage (V) and Power (S).

For example,
If the Impedance is 20 ohms with an angle of 3 degrees and the Current is 30 amps with 4 degrees, then the results will be;
Voltage – 600 Volts with 7 °phase angle, Power – 18000 with 3°phase angle, (R + jX) - 19.97+j1.05 and (P + jQ) - 17975.33+j942.05.

There are formulas which the calculators use to execute the conversions;

Formula of the Ohm's Law
V (V) = I (A) x R (Ω), which means that the voltage in volts is calculated by multiplication of the current in amps (A) by the resistance in ohms (Ω).

P (W) = V (V) x I (A), which means that the power in watts is calculated by multiplication of the voltage in volts by the current in amps (A).

Formula of the AC Ohm's Law
V (V) = I (A) x Z (Ω) = (\I\ x \Z\) ˂Ө I +ӨZ), which means that the voltage in volts is calculated by multiplication of the current in amps by the impedance in ohms.

S (VA) = V (V) x I (A) = (\V\ x \I\) ˂Ө V –ӨI), which means that the complex power in volt-amps is calculated by multiplying the voltage in volts by the current in amps.

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