Mixed Power Problems Calculator

Power Equations:

\[ P = V \times I \quad \text{or} \quad P = I^2 R \quad \text{or} \quad P = \frac{V^2}{R} \]

Power (P):

watts (W)

Voltage (V):

volts (V)

Current (I):

amperes (A)

Resistance (R):

ohms (Ω)

Calculation Results:

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1. What is Power Calculation?

Power calculation in electrical circuits involves determining the relationship between power, voltage, current, and resistance using fundamental electrical formulas. These calculations are essential for circuit design, analysis, and troubleshooting.

2. How Does the Calculator Work?

The calculator uses three fundamental power equations:

\[ P = V \times I \quad P = I^2 R \quad P = \frac{V^2}{R} \]

Where:

\( P \) — Power in watts (W)
\( V \) — Voltage in volts (V)
\( I \) — Current in amperes (A)
\( R \) — Resistance in ohms (Ω)

Explanation: The calculator automatically determines which parameters are known and calculates the missing values using the appropriate formulas from Ohm's Law and power relationships.

3. Importance of Power Calculation

Details: Accurate power calculation is crucial for circuit design, component selection, safety analysis, energy efficiency optimization, and preventing electrical overloads in systems.

4. Using the Calculator

Tips: Enter any two known values to calculate the remaining parameters. Ensure values are positive and in correct units. The calculator will automatically determine which formulas to apply based on the provided inputs.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between power, voltage, and current?
A: Power equals voltage multiplied by current (P = V × I). This is the fundamental relationship in DC circuits.

Q2: How do I calculate power when I know resistance and current?
A: Use P = I² × R. Square the current, multiply by resistance to get power in watts.

Q3: What if I know voltage and resistance but need power?
A: Use P = V² / R. Square the voltage, divide by resistance to calculate power.

Q4: Are these formulas applicable to AC circuits?
A: For resistive AC circuits, yes. For circuits with reactive components, additional factors like power factor must be considered.

Q5: What are typical power values in household circuits?
A: Household circuits typically handle 15-20 amps at 120V (1800-2400W). Larger appliances may require dedicated circuits with higher capacity.