A platinum resistance thermometer has resistance 2.2 Ω at 0°C and 5.6 Ω at 100°C. If its resistance is 7.3 Ω in a bath, find the temperature of the bath on the platinum resistance thermometer?

1 Answer
Mar 5, 2018

The temperature of the bath is #=150^@C#

Explanation:

The resistances are as follows :

#R_0=2.2Omega#

#R_100=5.6Omega#

The temperature coefficient of the platinum thermometer is

#alpha=(R_100-R_0)/(100-0)=(5.6-2.2)/(100)=0.034Omega^@C^-1#

Let the temperature of the bath be #=theta^@C#

#R_(theta)=7.3Omega#

Therefore,

#theta=(R_(theta)-R_0)/(alpha)=(7.3-2.2)/0.034=150^@C#