6. A solid uniform sphere of radius R and mass M has a rotational inertia about a diameter that is given by (2/5)MR². A light string of length 3R is attached to the surface and used to suspend the sphere from the ceiling. Its rotational inertia about the point of attachment at the ceiling is:
(A) (2/5)MR²
(B) 9MR²
(C) 16MR²
(D) 47/5MR²
(E) (82/5)MR².

答案:登入後查看
統計: 尚無統計資料

詳解 (共 2 筆)

#6378685
A solid uniform s...
(共 317 字,隱藏中)
前往觀看
0
0
#7412216
所以這題考得是平行軸定理
所以第一步先從題目中可以得到繞質心得轉動慣量為2/5mR^2
然後注意這裡的d是新轉軸和舊轉軸到質心得距離
題目給的是到表面的距離,所以要再加球的半徑R
所以加起來的答案為82/5mR^2
0
0