A steel beam is used in the construction of a skyscraper. By what fraction (change in L)/Lo does the length of the beam increase when the temperature changes from that on a cold winter day (-15 degree F) to that on a summer day (+ 105 degree F)?

I got 0.00144 for the answer, but it's not correct. Please give me teach me how to do this. THANKS A LOT!

1 answer

change in T = 120 deg F which is 120 (100/(212-32) ) = 120 * 5/9 = 66.7 deg C
delta L/L = [1.2*10^-5 ](66.7)
80.04 *10^-5
= .00080