CAPE Physics Unit 1 · 2017 · Paper 1 · Question Q32

The triple point of water is chosen as the upper fixed point on the thermodynamic scale of temperature rather than the melting point of ice because

1. (A)the thermodynamic scale is not an empirical scale
2. (B)it makes the scale more linear for gas thermometers
3. (C)the melting point of ice varies with the type of thermometer used to measure it
4. (D)it is precisely reproducible as it has only one possible temperature and pressure