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Force System Resultants

Resolving Forces in Moment Calculations

Description

The principle of moments, also called Varignon's theorem, explains how a force creates rotation about a point. It is a key idea in physics and engineering. It also helps describe when a rigid body stays in equilibrium under external forces.

The moment of a force is found by multiplying the force ...

Transcript

力矩原理,或称瓦里农定理,描述了刚体在力的作用下达到平衡的条件。

该定律指出,力对某一点的力矩等于该力的各个分量对该点的力矩之和。

力在某一点的力矩是力的作用点到该点的垂直距离与所施加力的乘积。

也可以通过将力分解为其分量,并将各个分量与相应的力臂相乘来确定。

考虑一个在管道上安装有手轮的阀门。当施加力以旋转手轮时,该力相对于中心的力矩可通过力的大小乘以从中心到力作用点的垂直距离来确定。

所施加的力也可分解为其分量,通过将每个力分量与其相应距离的乘积相加,即可求得力矩。