Question

In a thermometer, distance between the upper and lower fixed points is $80cm$, (a) Find the temperature on Celsius scale if the mercury level rises to a height $10.4cm$ above the lower fixed point. What will be the temperature recorded in part

Answer 1

Let the temperature be measured between the upper point ${100}^{o}C$ and lower point $0^{o}C$

a) Given the distance between upper and lower fixed points=$80cm$

i.e. $1cm=\frac{{100}^{o}C}{80}={1.25}^{o}C$

$1cm$ corresponds to ${1.25}^{o}C$

Given that the mercury level rises to a height $10.4cm$ above the lower fixed point

$\therefore temperature=10.4\times {1.25}^{o}C={13}^{o}C$

The temperature on celsius scale corresponding to mercury level of height 10.4cm=${13}^{o}C$

b) From celsius to fahrenheit scale

$\frac{f-32}{9}=\frac{C}{5}f=\frac{9C}{5}+32=\frac{9\times 13}{5}+32=55.4℉$

the temperature recorded on fahrengeit scale=$55.4℉$