Question

An ordinary mercury thermometer is first put in a beaker containing dry ice and is then transferred into another beaker containing hot water. The mercury thread rises four-fifth of the distance between the lower and upper fixed points. Find the temperature of water (i) in degree Celsius is m and (ii) in degree Fahrenheit is n then m+n =

Answer 1

In a mercury thermometer, the lower fixed point is $0^{o}C$ and upper fixed point is ${100}^{o}C$. The mercury thread rises four fifth of the distance between $0^{o}C$ and ${100}^{o}C$.

l) Four fifth of celsius scale

$=\frac{4}{5}\times {100}^{o}C$

$={80}^{o}C$

Temperature of water in celsius scale $={80}^{o}C$

ll) Temperature of water in fahrenheit scale

$=\frac{9\times 80}{5}+32=176℉$

where the conversion formula

$(f-32)/9=C/5$ is used