摘要:转动惯量分为定性和定量两个方面：定性方面的转动惯量是描述刚体在转动中的惯性大小的物理量：它们所获得的角加速度一般是不一样的，转动惯量大的物体所获得的角加速度小，即角速度改变的慢；转动惯量小的物体所获得的角加速度大，即角速度改变得块。在日常生活中有许多运动都已转动惯量有关，因此物体的转动惯量时值得研究的，特别是引起误差的因素。

　　　测量转动惯量的方法有很多，本文主要采用刚体转动、扭摆、三线摆三种方法进行研究，并对测量时引起误差的因素给予分析讨论。经过比较分析，把每个实验中实验值同理论值比较。分析结果得出：在三个实验中，刚体转动测量的相对误差为3.0％，三线摆的相对误差为1.5％，扭摆实验则达到19. 0％，三线摆实验是误差最小的。在三线摆中，摆角和摆长确定后，避免了摩擦阻力和平动而带来的误差。

关键词：刚体转动；三线摆；扭摆；误差分析

Abstract:Moment of inertia divided into qualitative and quantitative aspects: the qualitative aspect is to describe the rigid body moment of inertia of the rotating inertia in physical size; They generally do not get the same angular acceleration, moment of inertia obtained a large quantity of objects of small angular acceleration, angular velocity that is slowly changing;

Conversely, a small moment of inertia of rigid body angular acceleration obtained large, the angular velocity change quickly. In everyday life there are many sports moment of inertia are related to Therefore, the moment of inertia is an object worthy of study, particularly the factors that caused the error.

　　　Moment of Inertia Measurement There are many ways, this paper uses rigid body rotation, torsion, three-wire pendulum of three methods, and measurement errors caused by the factors discussed given. After a comparative analysis of the experimental value of each experiment compared with the theoretical value, the results can be found: In three experiments, the rigid body rotation of the minimum relative error of measurement 3.0%, three-wire placed in the minimum relative error is 1.5%, torsion pendulum experiment, To 19.0 percent. Three-wire pendulum is the smallest error. Three-wire pendulum in the pendulum angle and length are established, which will be able to avoid friction errors brought peace move.

Key words: Rigid body rotation; Three-wire pendulum; Torsion; Error analysis