Question

Two absolute scales A and B have triple points of water defined to be 200 A and 350 B. What is the relation between T_A and T_B?

Answer 1

Triple point of water is, T = 273.16 K

Since the absolute scales measure the triple point as 200 A and 350 B.

∴ 200A = 350B = 273.16 K

∴ 1A = \(\frac{273.16}{200}\)K and 1B = \(\frac{273.16}{350}\)K

If T_A and T_B are the temperatures on the two scales, then

\(\frac{273.16}{200}\)TA = \(\frac{273.16}{350}\)TB

∴ T_A = \(\frac{200}{350}\) T_B = \(\frac{4}{7}\)T_B

\(\frac{T_A}{T_B}=\frac{4}{7}\)

The relation between T_A and T_B is T_A : T_B = 4 : 7