A thermometer measures temperature. Old-school: a liquid (mercury or alcohol) expands up a tube. Modern: thermistor or infrared.
Type a value, pick units
36.6667
98 °F = 36.6667 °C
How it actually measures
Old liquid thermometers work because liquids expand when warmed — mercury or coloured alcohol rises in a thin tube past a printed scale. Modern ones use a thermistor (resistance changes with heat) or read infrared light an object emits — no contact needed.
Reference points worth knowing
- 0 °C / 32 °F — water freezes
- 37 °C / 98.6 °F — human body
- 100 °C / 212 °F — water boils (at sea level)
- −273.15 °C / 0 K — absolute zero, the coldest possible
Your turn
A thermometer reads 25 °C. Is that warm or cold for a room?