Meaning & use
ohm
Last updated
Meaning
nouncountabletechnical
The standard unit of electrical resistance, equal to the resistance that allows one ampere to flow when one volt is applied.
Grammar: Countable: you can say one ohm, two ohms, etc. Often used after a number without a plural ending in technical writing.
Patterns
- a resistance of X ohms
- measured in ohms
- an ohm of resistance
The resistor has a value of 100 ohms.
A speaker with an impedance of 8 ohms works well with this amplifier.
The multimeter showed a reading of 0.5 ohms, indicating a short circuit.
Word forms
| plural | ohms |
|---|
Common combinations
- ohm's law
- Ohm's law relates voltage, current, and resistance.
- a 10-ohm resistor
- You need a 10-ohm resistor for this circuit.
- measure in ohms
- Resistance is measured in ohms.
- high ohm
- Headphones with high ohm ratings need a powerful amplifier.
Word family
- ohmic adjective
- Describing a material or device that obeys Ohm's law.
Commonly confused: ohm or omega?
ohm vs omega
Omega is the Greek letter Ω, which is the symbol for the ohm, but omega also has other uses in mathematics and science.
Practice
What is the correct unit for measuring electrical resistance?
Choose one answer.
The ohm measures resistance. A volt measures electrical potential, an ampere measures current, and a watt measures power.
Make it your own
Write a sentence using “ohm”, then check it and compare it with the examples above.