What device can make pulling backbone cable easier in cable trays?

The choice of a pulley as the device that can make pulling backbone cable easier in cable trays is appropriate due to its ability to significantly reduce friction and allow for more controlled movement of heavy cables. A pulley system works by changing the direction of the force applied, enabling users to lift or pull heavy cables with less effort.

Using a pulley in a cable tray setup facilitates easier handling and positioning of cables, particularly in tight or awkward spaces where direct pulling might be challenging. Additionally, pulleys can be arranged in a way that distributes the weight of the cable more evenly, minimizing the risk of damage during installation.

While block and tackle systems are also designed to provide mechanical advantage, they are generally more complex and are used in scenarios where a significant reduction of force is necessary over a vertical distance. Cable guides assist in directing the cables but do not inherently reduce the effort needed to pull them. A winch is typically used for heavy lifting but may not be the most efficient option in confined spaces like cable trays, where a simple pulley can suffice.