Enter the total number of watts (watts) and the total current (amps) into the calculator to determine the Voltage from Watts. 

Voltage from Watts Formula

The following formula is used to calculate the Voltage from Watts. 

V = W / A

Variables:

  • Where V is the Voltage from Watts (volts)
  • W is the total number of watts (watts) 
  • A is the total current (amps) 

To calculate the voltage from watts, divide the wattage by the amperage.

How to Calculate Voltage from Watts?

The following two example problems outline the steps and information needed in order to calculate the Voltage from Watts.

Example Problem #1:

  1. First, determine the total  number of watts (watts). In this example, the total  number of watts (watts) is measured to be 31.
  2. Next, determine the total current (amps). For this problem, the total current (amps) is calculated to be 20.
  3. Finally, calculate the Voltage from Watts using the formula above: 

V = W / A

Inserting the values from above into the equation yields: 

V = 31 / 20 = 1.55 (volts)

FAQ

What is the significance of calculating voltage from watts?

Calculating voltage from watts is crucial in electrical engineering and electronics because it helps in designing circuits, selecting the right components, and ensuring the safety and efficiency of electrical systems. It allows engineers to understand the electrical potential that can be provided given a certain power (watts) and current (amps), which is fundamental in power distribution and consumption analysis.

Can I calculate voltage if only the power (in watts) is known, without current?

No, to calculate voltage from power (watts), you also need to know the current (in amps) flowing through the circuit. The relationship between power, voltage, and current is defined by the formula V = W / A, where V is voltage, W is power in watts, and A is current in amps. Without knowing the current, you cannot directly calculate the voltage from power.

Are there any limitations to using the V = W / A formula for calculating voltage?

Yes, the formula V = W / A assumes a linear relationship and does not account for phase differences between current and voltage in AC circuits or power factor considerations. It is most accurate for direct current (DC) circuits or for AC circuits where the power factor is close to 1. For more complex AC circuits, additional factors such as reactance and power factor must be considered for accurate voltage calculations.