IBEW Apprenticeship 1st Year, 3rd Period (1-3) Practice Test 2026 - Free IBEW Apprenticeship Practice Questions and Study Guide

Wire rope is composed of various strands that are laid around a central core to provide strength and flexibility. The central core can be either an Independent Wire Rope Core (IWRC) or a fiber core. A fiber core consists of materials like natural fibers or synthetic fibers which aid in maintaining the shape of the wire rope while providing a level of cushioning and insulation from abrasion.

Choosing a fiber core has some advantages; it can reduce the weight of the rope, which may be beneficial in specific applications where weight is a factor. It can also enhance the rope's ability to absorb vibrations, and in environments where moisture is present, fiber cores can offer some resistance to the ingress of water.

The other options, such as plastic, steel, and composite, typically serve different purposes or aren't standard as central cores for wire rope strands in the same context as IWRC or fiber. Plastic cores are less commonly used due to their limitations in strength and heat resistance, steel cores primarily refer to IWRC, and composite cores may not have the same historical precedent or application in traditional wire rope design.