Question

A faulty mercury in glass thermometer indicate that the ice point of pure water is 0.8°c and steam point is 99.5°c under standard atmospheric pressure.Deduce an expression in the form of y=mx +c,where m and c are constant to relate the faulty temperature reading F°c to the correct temperature T°c

Answer 1

Correct temperature of steam point is 100 ^oC and ice point is 0 ^oC

let x be the fault temperature and y be the correct temperature

when y=0 and x=0.8 then

$0=m\times0.8+c\ \ \ \ \ \ \ ........(1)$

$c=-0.8m$

when y=100 and x=99.5

$100=99.5m+c$

substituting the value of c here

100=99.5m-0.8m=98.7 m

m =1.0131

c =-0.81