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수학동아 - 폴리매스
함께 풀고 싶은 문제
창의력을 기를 수 있는 수학 문제 또는 퍼즐을 내는 곳입니다.
여백 패르마
2020.07.24 22:46
조회 649
지표면에서 R만큼 떨어진 점 P를 집자. 점 P에서 지표면어 내린 수선의 발을 X라 하자. 선분 PX위에 있는 점 Q에 대해 선분 PQ의 길이는 r이다.
점 Q에 질량 m인 입자를 올려놓자. 이 입자는 선분 PX위에 움직인다. 이 입자는 P에서 X로 움직이고, 운동시 가속도는 
(
는 입자에서 P까지의 거리이다.)
입자가 점 X에 도착할 때 까지 걸리는 시간을 구하시오.
(단, 미분방정식으로 풀지 마시오. )
지금 바로
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