EXPLANATION
Question: Which unit is used to measure temperature in the SI system?
- a) Celsius
- b) Fahrenheit
- c) Kelvin
- d) Rankine
ANSWER: c) Kelvin
EXPLANATION:
The unit used to measure temperature in the SI (International System of Units) system is the Kelvin (symbol: K). The Kelvin scale is an absolute temperature scale where zero Kelvin (0 K) represents absolute zero, the theoretically lowest possible temperature. The Kelvin scale is based on the same interval size as the Celsius scale, with the only difference being the reference point. While the Celsius scale uses 0 degrees Celsius (0 °C) as the freezing point of water and 100 degrees Celsius (100 °C) as the boiling point of water at standard atmospheric pressure, the Kelvin scale starts at absolute zero, which is approximately -273.15 degrees Celsius.
