🎓 Physics • Electricity
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Voltage Calculator
Solves electrical potential difference V in Volts from current and resistance, or power and current.
Ohm’s Law & Electrical Power Calculator
Enter any 2 known values — the remaining 2 are solved instantly via V = IR and P = VI.
Standard Circuit Presets:
Unit: V
Unit: A
Unit: Ohms (Ω)
Unit: W (J/s)
Dynamic DC Circuit SchematicConventional Current Flow (Clockwise)
Voltage (V)
12 V
Current (I)
2 A
Resistance (R)
6 Ω
Power (P)
24 W
Step-by-Step Derivation
Given: Voltage V = 12 V, Current I = 2 A
1. Resistance: R = V / I = 12 / 2 = 6.0000 Ω
2. Power: P = V × I = 12 × 2 = 24.0000 W
What is Voltage?
Voltage is electric potential difference, measuring the work required per unit charge to move a test charge between two points.
Formula & Step-by-Step Calculation
V = I × R
Current in Amperes times Resistance in Ohms.
Worked Step-by-Step Examples
Example 1
Current 3 A through 40 Ω resistance
Solution: 120 Volts
• 3 A × 40 Ω = 120 V
Common Real-World & Academic Use Cases
- ✓ Power supply voltage drops
- ✓ Battery voltage checks
- ✓ Circuit component bias voltages
How to Use the Voltage Calculator
1
Enter I and R
Input Current and Resistance.
2
Read Volts
View calculated voltage.
Frequently Asked Questions
Q: What is a Volt?
1 Volt = 1 Joule per Coulomb (J/C).