Voltage, current, resistance
For an ideal resistor under fixed conditions, Ohm’s law connects three quantities: V = I × R.
In 30 seconds
- Voltage is measured in volts, current in amperes, resistance in ohms.
- At fixed voltage, increasing resistance reduces current.
- Real components may heat up or behave nonlinearly.
Make it concrete
In a simulation, 12 V across 6 Ω gives 2 A and 24 W. Try doubling the resistance while keeping the same voltage.
Change a value. Watch the relationship.
Ideal steady DC resistor. Markers follow conventional current from + to −; their rate is proportional to I. They do not represent the literal speed of electrons. No thermal or wiring effects.
Check your understanding
At fixed voltage, does doubling an ideal resistance halve the current?
- Voltage is measured in volts, current in amperes, resistance in ohms.
- At fixed voltage, increasing resistance reduces current.
- Real components may heat up or behave nonlinearly.
Go to the source
Sources reviewed: 13.09.2026