수학동아 - 폴리매스

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함께 풀고 싶은 문제

창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.

[창의 퍼즐] 슬라이딩

아인수타인 2019.11.25 06:19 조회 521

문제 푼 사람 0명

페이스북 트위터 카카오톡 카카오스토리 네이버블로그 네이버밴드

야구든, 아니면 다른 운동이든 1등하기 위해 마지막 구간에서 슬라이딩하는 모습을 본 적 있을 것이다. 페루마는 야구를 하고 있는데 이번에 3루에 있는 페루마만 홈으로 들어오면 페루마 팀이 이긴다. 반대로 이번에 페루마가 아웃되면 페루마 팀이 진다. 이런 상황에서 현재 공이 거의 포수에게 들어오기 직전이라 태그만 당하면 진다. 그래서 페루마는 슬라이딩 기법을 쓰려고 한다. 그런데 홈보다 더 적게 미끄러지면 안 된다. 페루마는 달리기를 하면 $1m/s^2$ 으로 가속되고, 슬라이딩하면 $-0.1m/s^2$ 으로 감속한다. (단, 속도는 항상 양수이다.) 제 3루에서 홈까지의 거리는 100m일 때, 페루마는 3루에서 출발하고 최소 몇 초 후에 슬라이딩을 해야 할까? (단, 페루마가 3루에서 출발하는 순간 속력은 0이다.)

이전글 초딩과 중딩의 대답 7탄

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