Cantilevers and Extension

Rest Length Separates Excess

A rest length separates total extension from excess stretch. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Rest length is not the same as extension

The tether extension is 6 metres, while the rest length is 4 metres.

6−46\mathbin{-}4
Tether extension ledgerAnchor and bead positions define extension.anchorbeadextensionexcess

Excess extension is the stretch beyond rest

The excess extension is 2 metres.

6−4=26\mathbin{-}4=2
Tether extension ledgerAnchor and bead positions define extension.anchorbeadextensionexcess