Question

FULL SCREEN PRINTER VERSION BACK NEXT If we decrease the temperature, the strip bends in the other direction. A similar temperature dependence is behind the familiar liquid-in-glass thermometers, based on the fact that liquids such as mercury and alcohol expand to a different (greater) extent than their glass containers Linear Expansion If the temperature of a metal rod of length L is raised by an amount At its length is found to increase by an amount AL - La AT (18.3.1) in which a is a constant called the coefficient of linear expansion. The coefficient a has the unit "per degree" or "per kelvin" (recall that they are equivalent) and depends on the material. Although a varies somewhat with temperature, for most practical purposes it can be taken as constant for a particular material. The thermal expansion of a solidks like photographic enlargement except it is in three dimensions. This next figure shows the (exaggerated) thermal expansion of a steel ruler. 3 4 (e) 5 6 → Circle Circular hole 6 7

The first three pictures go together, but I just need help with question 2. Then the last picture is seperate

Answer 1

AT solution 2 Here Li= 4(ltaat) Lz' = 12 (1+RAT) Son Area, 'A' - Li'le' IL (1+401) •12 (1+241) Az Lila 1+297)? --Ella [1472AT? +2R AT] A = 1, L2 [1 + 220T +?AT?] expanded