Waves units
- Syllabus
- 2024
- Topic
- —
- Level
- —
Learning objectives
Choose the correct unit for waves
A wave measurement is complete only when its unit identifies the quantity being measured. The required unit symbols are case-sensitive and are written after the numerical value.
| Wave quantity or context | Unit | Unit symbol | Example |
|---|---|---|---|
| angle | degree | ∘ | 35∘ |
| frequency | hertz | Hz | 50 Hz |
| wavelength or distance | metre | m | 0.80 m |
| wave speed | metre per second | m/s | 340 m/s |
| time or period | second | s | 0.020 s |
Hertz is a rate unit: 1 Hz means one cycle per second. Metres measure length, while metres per second measure speed. Seconds measure a time interval, including the time for one cycle when a period is stated.
Do not confuse a quantity symbol with its unit: frequency may be represented by f but is measured in Hz; wave speed may be represented by v but is measured in m/s. Write Hz with a capital H, but m and s in lower case.