About Resistor Wattage Calculator

The Resistor Wattage Calculator helps you determine the power dissipation and resistance of a resistor based on the voltage across it and the current flowing through it.

Power dissipation in a resistor is a crucial factor to consider in circuit design to ensure that the resistor can safely handle the electrical power without overheating.

Formula

Power (Wattage):

The power dissipation (\(P\)) of a resistor is given by:

\[P = V \times I\]

Where:

• \(P\): Power dissipation in watts (W)
• \(V\): Voltage across the resistor in volts (V)
• \(I\): Current through the resistor in amperes (A)

Resistance:

The resistance (\(R\)) of the resistor is calculated using Ohm’s Law:

\[R = \frac{V}{I}\]

Where:

• \(R\): Resistance in ohms (Ω)
• \(V\): Voltage across the resistor in volts (V)
• \(I\): Current through the resistor in amperes (A)

Example Calculation

Let’s consider an example:

• Voltage (\(V\)): 12 V
• Current (\(I\)): 2 A

Step 1: Calculate Wattage

Using the formula \(P = V \times I\):

\[P = 12 \, \text{V} \times 2 \, \text{A} = 24 \, \text{W}\]

Step 2: Calculate Resistance

Using the formula \(R = V / I\):

\[R = \frac{12 \, \text{V}}{2 \, \text{A}} = 6 \, \Omega\]

The power dissipation of the resistor is 24 W, and its resistance is 6 Ω.