Physics help please!!?

2016-02-25 4:37 pm
Show that the moment of inertia of a uniform rod of length L and mass M about an axis perpendicular to the
rod and passing through its center of mass is
1/12*ML^2

回答 (1)

2016-02-25 6:16 pm
✔ 最佳答案
Let's say the rod has uniform mass density λ = M/L
where M is the mass and L the length.

MoI I = ∫ x² dm = ∫ x² * λ dx = λ ∫ x² dx →evaluated from -L/2 to L/2
I = λ * x³/3 |[-L/2,L/2] = λ/3 * (L³/8 - -L³/8) = λ/3 * L³/4
When we substitute λ = M/L, we get
I = (M / 3L) * L³/4 = ML² / 12 ◄
QED

Hope this helps!


收錄日期: 2021-04-21 17:05:32
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20160225083722AACoiux

檢視 Wayback Machine 備份