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- Arc strikes outside of the welds were avoided .
- The beam will deflect into a circular arc .
- Arc lamps require a current-limiting ballast .
- The individual arcs cannot be rectified .
- The pole swung in an arc .
- A common laboratory source of light is provided by a mercury arc .
- The indegree of a vertex v in d is the number of arcs with head .
- If the diameter of the pupil is 6 mm the eye is able to separate 120 seconds of arc .
- The crack between the coped and hole was removed by air arc and then repaired by welding .
- A radian is the angle subtended by an arc of a circle whose length is just equal to the radius .