P: Talking about one popular myth in Archaeology, some people simply think excavation is digging the site until something valuable is found. Well while there is an element of luck involved, we have an array of high tech devices to help us figure out where to put our efforts. You know, we can’t just dig up the site randomly looking for an ancient structure. There is one of the newer tools actually created by a different field of study. The machine relies on particle physics. Um... interdisciplinary I’d say. And it is called a muon detector, or counter. Muon is a charged elementary particle similar to electron.
Okay, let me start over. On Earth, most naturally occurring muons are created by cosmic rays, which consist mostly of protons, many arriving from deep space at very high energy. When these charged particles of cosmic rays collide with molecules in the upper atmosphere, they break up into smaller particles, muons. Traveling at the speed of light, muons can penetrate tens of meters into rocks and other matters on earth’s surface. In fact, they can pass through solid matter, so they can transmit deep into the surface. Thus, this property of muon is perfect for archaeologists to take advantage of.

1. What is the lecture mainly about?
(A) Misconceptions about muon detectors in Archaeology
(B) An excavation of an ancient structure using a muon detector
(C) The collaboration between physicists and archaeologists in the development of the muon detector
(D) Benefits that archaeologists can obtain from muon detectors

[Main Idea Q]
- main idea Q으로서, 첫 번째 문제로 등장한다.

[해설]

- 도입부에서 를 소개하고 있다. 전형적으로, main topic 을 소개하고 나서는 이 main topic 을 부연설명한다.
- main topic 을 부연설명하고 나서 main idea 를 언급한다.
- 즉, muon detector(main topic ) 소개 → muon 설명( main topic 부연설명) → muon detector 기능(본론) →
- signal 로는 이다. 뒤에 오늘의 main idea 이다.

정답: (D)

[오답분석]

- A는 첫 문장으로 한번 언급된 것이다. 그러므로 해서 답이 되지 않는다
- B도 역시 ancient structure (Pyramid) 를 예시로 언급했지만, excavation 에 대해서는 언급하지 않았다. 설사, 언급했다 하더라도, too specific 해서 답이 되지 않는다.
- C도 too specific 해서 답이 될 수 없다.