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Force System Resultants

Torque on a Flywheel: Direction and Size

Description

Torque, or the moment of a force, describes how a force can make an object turn about an axis. It is a vector quantity, so it has both size and direction. This idea is important in physics, mechanics, and engineering.

A simple flywheel example shows how torque works. The flywheel rotates about po...

Transcript

力矩,或称力的矩,是指力使物体绕某一点或轴线(该点或轴线不在力的作用线上)发生转动的能力。它是一个矢量量。

以一个飞轮为例,施加一个力使飞轮绕点 O 旋转。

此处,力臂是指从点 O 到力的作用线的垂直距离。

力的大小乘以力臂得到力矩的大小。因此,力矩的单位是牛顿·米。

当施加的力与飞轮相切时,其量值达到最大。

右手定则用于确定力矩的方向。如果弯曲的手指表示力矩引起的旋转方向,则拇指表示力矩的方向。

通常情况下,正力矩表示飞轮的逆时针旋转,而负号表示飞轮的顺时针旋转。