We could design a very simple temperature gage using two axial bars with different COTE. In the

figure below, the bar on the left has a length of $5$ cm with a COTE of $5$ x $10-6$

$/$ o C$.$ The bar on the

right is also originally at a length of $5$ cm with a COTE of $9$ x $10-6$

$/$ o C$.$ The bars are fixed at ground

and are $4$ cm apart. A rigid horizontal arrow is pinned to the top of each bar at B and C and is $12$

cm long from B to D$.$ If we increase the temperature $10$ degrees C$,$ how much has point D moved

above its original position? Note: There is only thermal axial deformation for each bar equal to

$!"$TL$.$ Your job is to find out how far B and C move vertically, and then use similar triangles

$($again$!)$ to get the final position of D $($see the dashed line for the rough final position of the

arrow$).$ A drawing of this deflected horizontal arrow will help you a lot. Ans: $85$ x $10-5$

cm