問題詳情
52. A solid brass ball of mass 0.280 g will roll smoothly along a loop-the-loop track when released from rest along the straightsection. The circular loop has radius R = 14.0 cm, and the ball has radius r << R. What is h if the ball is on the verge of leavingthe track when it reaches the top of the loop?
(A) 47.8 cm
(B) 27.8 cm
(C) 57.8 cm
(D) 37.8 cm
(E) 78.3 cm