Question
A platinum resistance thermometer has a resistance of 10.59ohms at 0 degree celcius and 15.59ohms at 100 degree celcius. Assuming that the resistance changes uniformly with temperature, what is: (i) the temperature when the resistance is 10.59ohms? (ii) the resistance of the thermometer when the temperature is 55degree celcius?
Answers
Dr Russ
i) is easy as that is in the question and is a prompt for the next part:
As we are told that response is linear the equation for the resistance will be of the form
y=mx+c or
R=mT+c if you like
we are told c in the question (c=10.59 ohms)
to calculate m
m=(15.59-10.59)ohms/100 C
= 0.0500 ohms/C so the equation is
R=0.0500T+10.59
Now substitute 55 deg C and calculate R
As we are told that response is linear the equation for the resistance will be of the form
y=mx+c or
R=mT+c if you like
we are told c in the question (c=10.59 ohms)
to calculate m
m=(15.59-10.59)ohms/100 C
= 0.0500 ohms/C so the equation is
R=0.0500T+10.59
Now substitute 55 deg C and calculate R