Mechanics · Moments
Chapter 1 · 3
The idea
Non-uniform rods and tilting
Beams whose weight does not act at the centre — finding the weight or the position of the centre of mass by taking moments — and "on the point of tilting" problems, where the reaction at the support about to be left is zero.
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Mechanics · Moments
Non-uniform rods and tilting
Beams whose weight does not act at the centre — finding the weight or the position of the centre of mass by taking moments — and "on the point of tilting" problems, where the reaction at the support about to be left is zero.
Why it works
The centre of mass is now an unknown
Pick up a sledgehammer by the middle and it dips hard to one side — its weight doesn't act at its midpoint. A uniform rod has its weight at the centre; a non-uniform one does not — thicker at one end, or loaded unevenly. Its whole weight still acts at a single point, the centre of mass, but you don't know where that is in advance. Moments let you find it. For a flat shape, a frame or a set of particles, see Centres of mass of laminas, frameworks and particles.Keep reading — free
The rest of the explanation, plus 3 worked examples you step through move by move.
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