Strips 10.000 cm wide are to be cut from a thin sheet copper. The copper sheets
ID: 1537263 • Letter: S
Question
Strips 10.000 cm wide are to be cut from a thin sheet copper. The copper sheets are unloaded into the cutting area in an of industrial high bay when the cutting area temperature is 70 degree F. The cutter gets called away for a meeting. On returning from the meeting, the cutter sets the saw to a 10.000 cm width and begins the work. The temperature is now 90 degree F. After cutting the strips, the pieces are loaded into a truck whose inside temperature is 120 degree F, and hauled to the client. The client places the strips climate-controlled warehouse whose temperature is a constant 60 degree F, takes them out a month later, and measures them. What width are the strips when measured by the client?Explanation / Answer
Let us assume the coefficient of expansion as 'a'.
at 70 F length = 10.00 cm
at 90F length = 10(1+20a) = l'
l' =10 cm at 90F
Length at 60 F
is
l'(1-30a)
where l'=10.0 cm and a is the coefficient of expansion per F of copper