Enter the total emf (volts), the current (amps), and the resistance (ohms) into the calculator to determine the Terminal Voltage.

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## Terminal Voltage Formula

The following formula is used to calculate the Terminal Voltage.

Vt = emf - I * R

- Where Vt is the Terminal Voltage (volts)
- emf is the total emf (volts)
- I is the current (amps)
- R is the resistance (ohms)

To calculate terminal voltage, subtract the product of the current and the resistance from the total emf.

## How to Calculate Terminal Voltage?

The following example problems outline how to calculate the Terminal Voltage.

**Example Problem #1**

- First, determine the total emf (volts). In this example, the total emf (volts) is determined to be 100 .
- Next, determine the current (amps). For this problem, the current (amps) is measured to be 5 .
- Next, determine the resistance (ohms). In this case, the resistance (ohms) is found to be 3.
- Finally, calculate the Terminal Voltage using the formula above:

Vt = emf – I * R

Inserting the values from above into the equation gives:

Vt = 100 – 5 * 3 = 85 (volts)

**Example Problem #2**

Using the same method as above, determine the variables required by the equation. For this example problem, these are provided as follows:

total emf (volts) = 150

current (amps) = 2

resistance (ohms) = 20

Entering these given values into the calculator above yields:

Vt = 150 – 2 * 20 = 110 (volts)