Loci

A locus is the path traced by a point as it moves according to specific rules or conditions. Think of it like the track left by a football rolling across a field—that path is a locus. In technical drawing, we study different types of loci because they appear everywhere in real life and engineering design.

The common loci you'll encounter include straight lines, circles, ellipses, parabolas, and hyperbolas. A cycloid, for example, is the path traced by a point on a wheel's rim as the wheel rolls along a straight line—exactly like the motion of a point on a bicycle tyre as you ride down the road in Lagos. Spirals appear in watch springs and ceiling fans common in Nigerian homes. Helixes describe the shape of springs and screws.

Understanding these curves helps engineers design everything from machine parts to architectural structures. You must master the construction methods for each locus type because the WAEC exam always includes loci questions requiring accurate geometric drawings.