The resistances corresponding to the lower and the uppper fixed points, in a platinum resistance thermometer are `3.50Omegaand3.65Omega`. What would be the resistance at a temperature equal to the freezing point of mercury `(-37^(@)C)`?

Explanation

Given `R_(0) =3.50 Omega , R_(100) = 3.65 Omega and t = - 37^@C , R_(t) = ? `
`:.` Using `t=[(R_t-R_0)/(R_(100)-R_0)]100^@C`
We have , `-37^@C=[(R_(t)-3.50)/(3.65-3.50)]100^@CimpliesR_(t)-3.50=-0.056impliesR_(t)=3.55Omega`
`:.` The required resistance is `3.55 Omega` .