Electricity & Magnetism
Ohm's Law
Ohm's Law for ohmic conductors.
Variables
VV
Voltage
Potential difference
In SI units: kg·m²/(A·s³)
IA
Current
Electric current
RΩ
Resistance
Electrical resistance
In SI units: kg·m²/(A²·s³)
Allowed values: 0 or more
Derivation
Empirical relationship for ohmic materials.
Your notes
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Check value
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- I = 2 A (Current)
- R = 3 Ω (Resistance)
Result: V = 6 V
Other electricity & magnetism formulas with the same quantities
- Electric Current (Electric Circuits) shares Current
- Resistance (Electric Circuits) shares Resistance
- Capacitance (Capacitance) shares Voltage
- Capacitor Energy (Capacitance) shares Voltage
- RC Time Constant (Capacitance) shares Resistance
- Magnetic Force on Wire (Magnetism) shares Current
Where this formula is listed
- Electricity & Magnetism formulas, under Electric Circuits, alongside Kirchhoff's Voltage Law and Kirchhoff's Current Law.
- In the electricity & magnetism list it comes after Electric Flux and before Electric Power.
- Electricity & Magnetism formula sheet, one of 48 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Ohm's Law formula?
Ohm's Law is written V = IR. Ohm's Law for ohmic conductors. It belongs to Electricity & Magnetism, under Electric Circuits.
What are the units in V = IR?
In SI units, V is voltage, measured in kg·m²/(A·s³); I is current, measured in A; R is resistance, measured in kg·m²/(A²·s³).
How is the Ohm's Law formula derived?
Empirical relationship for ohmic materials. The result is V = IR.