# Find temperature rise of Cylinder from Linear Thermal Coefficients

1. Sep 30, 2012

### poul

1. The problem statement, all variables and given/known data

Part 1: I have a cylinder of radius R and lengh L. At first i can assume that we have expansion in both R and L. And that i can use the linear thermal expansion coefficient(\alpha) = 4 \times 10^{-6}. The relative change in R and L is 1 \times 10^{-4}, and from that i have to find the temperature rise.

Part 2: Now we also to assume that the change in L is 0, and the relative change in R is again 1 \times 10^{-4}. So we only have expansion in R, and can assume the same linear thermal expanssion coefficients.

3. The attempt at a solution
Part 1: For this one we can use \times 10^{-4} = 4 \times 10^{-6}* \Delta T and find: \Delta T = 25 K.

Part 2: So for this one i just use? \times 10^{-4} = 3/2 \times 4 \times 10^{-6}* \Delta T and find: \Delta T = 16.67 K. Assuming small changes?