Most people are unaware that the magnitude-8.9 earthquake that struck Japan in March 2011 was actually the aftershock of a much weaker magnitude-7.2 quake that occurred two days earlier. While it may seem strange that a weak quake can cause a stronger aftershock, it is actually quite common. Earthquakes represent the release of stored up elastic strain energy, which builds as tectonic plates in the Earth’s crust slide over each other along the plane of the fault between them. Asperities and other irregularities along the surface of the fault create strain as certain parts of the plate become stuck while other parts continue moving. When the stress has risen enough to break through the asperity, the stored energy is released. Only about 10% of the stored energy actually manifests as seismic activity; the rest either causes fractures or widens preexisting fractures, or is converted into heat generated by friction. While earthquakes do represent the release of energy, the resultant seismic shifts can actually lead to situations of greater potential energy in the system as a whole, as if the quake caused a great weight to drop on a coiled spring. When this stress is released in the form of seismic activity, the resultant aftershock is likely to be greater in magnitude than the foreshock that caused it.
The author of the passage uses the metaphor of the coiled spring to
A. illustrate how tectonic plates can compress each other
B. provide an example of a physical situation distinct from that involved in earthquakes
C. demonstrate the thermodynamic phenomenon of potential energy entering a system
D. emphasize the similarities between various thermodynamic principles
E. clarify the relationship between potential energy and depleted energy
答案是B，在其他几个选项中，B确实是相对来说更正确的。但是文中没有一处地方提到了thermodynamic，这难道不算无中生有？ 感觉属于one word wrong. 求解答。作者: mailliw1 时间: 2013-9-2 17:42:22
都开学了？没人？作者: dula55 时间: 2013-9-2 19:02:45
原文中提到了“or is converted into heat generated by friction. ”，这就是热力动力学。
当让不是重点，答案很明显是B