本题目来源于试卷: 2012美国US F=MA物理竞赛，类别为 美国F=MA物理竞赛
[单选题]
An equilateral triangle is sitti f /xuxea190i7ue 0fcnng oo6mm.:scby 3,l ;rue ye me39semq *c*n an inclined plane. Friction is too high for it to slide under any circumstance, but if the plane is sloped enough it can "topple" down the hill. What angle incline is necessary for it to start mo3eelmq.y,:s s9em*;ymue*63c rb c toppling?
A. $30$ degrees
B. $45$ degrees
C. $60$ degrees
D. It will topple at any angle more than zero
E. It can never topple if it cannot slide
参考答案: C
本题详细解析:
Toppling occurs when the vertical li*b6kzpws; b a5ne passing through the object's center of mass (CM) falls outside its base of support. For an equilateral triangle, the CM is at its geometb6apz*;5b ks wric center. It will topple about its lower corner. The angle from the base to the line connecting the CM and the corner is $60^\circ$. When the incline angle equals this angle, the CM is vertically aligned with the pivot point, and any further increase will cause it to topple.
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