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함께 풀고 싶은 문제
창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.
[창의 퍼즐] [물리] 실수하기 쉬운 문제
아인수타인 2020.07.14 05:52 조회 676
문제 푼 사람 0명
공유하기
페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

(1) 아래처럼 빨간색 실이 천장에 매달려 있는 고정도르래가 있다. 빨간색 실의 장력은 얼마인가?

(2) 혹시 위 문제에서 100N이라 답했는가? 그러면 아래 상황을 생각해 보자.

여기에선 빨간색 실의 장력은 약 얼마인가? 아직도 좀 헷갈리는가? 그렇다면 도르래가 아니라 여러분의 팔에 실을 매달고 한쪽엔 겁나 무거운 아파트를 하나 매달고 다른 한쪽엔 그저 2kg의 물체가 매달려 있다고 생각해봐라. 과연 여러분의 팔은 부러지겠는가?

(3) 그러면 1번 문제에서 계산해서 답이 100N보다 작다는 것을 알아냈다면, 왜 100N보다 작은가? 계산해보니 100N보다 작게 나온 건 맞지만, 이걸 사전에 계산해보지 않고 알 수 있을까?

 

(모든 문제는 풀이 필수이며, 중력가속도는 10m/s^2이고, 모든 마찰력 및 공기 저항과 도르래 질량, 실의 질량은 무시한다.)

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    Byzantium Lv.6 2020.07.14 06:18 비밀댓글

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      아인수타인 Lv.12 2020.07.14 10:27 비밀댓글
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