大学物理的力学基本定律（二）-刚体力学和狭义相对论 大学物理学的清华版2
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这时mgl/2=βml²/3，得β=3g/2l，
转到竖直位置时，势能全转化为动能，有mgl/2=Jω²/2=ml²ω²/6，
得ω=√(3g/l)
祝愉快
第一问
1/2mgl=1/12ml^2乘以β 可以得出加速度β=6g/l
第二问
1/2mgl=1/12ml^2乘以ω^2 可以得出角速度ω=根号下6g/l
绛旓細杩欐椂mgl/2=尾ml²/3锛屽緱尾=3g/2l锛岃浆鍒扮珫鐩翠綅缃椂锛屽娍鑳藉叏杞寲涓哄姩鑳斤紝鏈塵gl/2=J蠅²/2=ml²蠅²/6锛屽緱蠅=鈭(3g/l)绁濇剦蹇
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