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[자유 기사] 삼각형을 이용한 구조물이 왜 많을까?
니유토갬 2020.05.29 19:25

사빗치즈의 집에 택배가 왔다.

그런데? 박스의 단면에도 삼각형 구조로 되어있고, 이상하게도, 다리나, 배의 돛에도 삼각형이 사용되고 있었다.

모두 왜 삼각형이 이 구조에 사용되는지 한번쯤 생각했을 것이다.

먼저 결론부터 말하자면, 삼각형은 다른 도형보다 재료의 양에 비해 무게를 지탱하는 힘이 강하기 때문이다.

그렇다면 이 구조를 무엇이라고 할까?

이 구조는 트러스 구조라고 하는데, 대표적으로 철도교로, 보행자 도관용, 고층 빌딩 그 중에서도 에펠탑도 트러스 구조이다.

앞에서 배의 돛이 삼각형이라고 말했다.

그러나, 초등학교 사회 교과서에도 나오는 내용인데, 판옥선은 직사각형처럼 생긴 돛을 달고 있다.

이처럼 옛날에는 그렇게 사용했지만, 알고보니, 힘이 좋지도 않고, 효율이 좋지도 않아서 사용하지 않게 되었다고 한다.

직사각형 모양의 돛을 달고다니던 배는 오직 항력(위키백과: 물체가 유체 내를 움직일 때 이 움직임에 저항하는 힘)을 이용해서만(배가 그냥 밀려가는 듯한) 나아갔다.

이렇게 그냥 밀려나가 듯이만 가면, 상황에 따라 달라지는 것이다.

필요에 따라 사람들은 돛을 만들었다.

우리도 주변을 잘 살펴보면 이 세상을 발전시켜나갈 수 있지 않을까?

대표 이미지 출처: http://strana.donga.ac.kr/lecture/sa1/sa1_note_ch4.pdf   (동아 대학교 토목공학과)

참고물: YTN SCIENCEhttps://www.youtube.com/watch?v=xuv2tWGAQ8s

 

 

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