Measuring something that curves
A bangle is curved. A straight ruler cannot bend to fit it.
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Step 1 of 4
- A curved bangle.
- Wrap a thread along the curve. Mark where it ends.
- Pull the thread straight.
- Lay it against a ruler and read it.
Rule: Lay a thread along the curve. Mark the thread where the curve ends. Straighten the thread. Measure it like any length: far end − near end.
A thread bends, so it can lie along the curve. The near end is the start of the thread. The far end is your mark.
The same method works for a plate's rim or a leaf's edge.