Ncert Exercises & Solutions

11.2 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 $T_{B}$ ?

Given:

The triple point of water on absolute scale A, T $_{1}$ = 200 A

The triple point of water on absolute scale B, T $_{2}$ = 350 B

The triple point of water on the Kelvin scale, $T_{K}$ = 273.15 K

The temperature of 273.15 K on the Kelvin scale is equivalent to 200 A on absolute scale A.

$T_{1}$ = $T_{K}$

200 A = 273.15 K

$∴ A = \frac{273.15}{200}$

The temperature of 273.15 K on the Kelvin scale is equivalent to 350 B on absolute scale B.

$T_{2}$ = $T_{K}$

350 B = 273.15

$∴ B = \frac{273.15}{350}$

If,

T $_{A}$ is the triple point of water on scale A.

T $_{B}$ is the triple point of water on scale B.

$∴ \frac{273.15}{200} \times T_{A} = \frac{273.15}{350} \times T_{B} T_{A} = \frac{200}{350} T_{B}$