Which one of the following is an example of a difficulty caused by thermal expansion?
A. buckled railroad tracks on a hot day
B. sagging power lines on a cold day
C. milkshakes melting
D. paint chipping off the side of a house
really appreciate it!!
2007-06-16 09:29:01 · 5 answers · asked by sunny 1 in Science & Mathematics ➔ Physics
One of these answers is an example of a phase change. One has nothing to do with temperature. On talks about cold temperatures. The last one talks about hot temperatures. Which one correctly explains thermal expansion?
2007-06-16 09:34:35 · answer #1 · answered by msi_cord 7 · 0⤊ 0⤋
A - Buckled railroad tracks. Metal expands when heated. If the expansion joints between rail segments are insufficient to contain the metal expansion, it buckles.
B - Likewise, powerlines "rise" on extremely cold days as the wire contracts (unless it is overloaded with snow, ice, or birds and squirrels)
C - The ice actually contracts as it melts - water is denser than water ice (few substances contract when they go from solid to liquid)
D - Paint chips because the oil or water inside the paint dries over time, or the underlying substructure shifts or dries, causing the paint to crack and fall away.
2007-06-16 09:39:18 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Clue - you mentioned the answer 3 times in your question in bold.
2007-06-16 09:39:41 · answer #3 · answered by Tsumego 5 · 0⤊ 2⤋
the answer is A
2007-06-16 10:00:21 · answer #4 · answered by Anonymous · 0⤊ 0⤋
A.
2007-06-16 10:30:22 · answer #5 · answered by Anonymous · 0⤊ 0⤋