Mechanics Practice Exam 2026 - Free Mechanics Practice Questions and Study Guide

When changing the sling angle from 60° to 30° during hoisting and rigging, the correct answer highlights the relationship between the sling angle and the tension within the sling. As the angle decreases, the tension in the sling increases.

At a 30° angle, the vertical component of the force that the sling must support remains the same (i.e., the weight of the load), but because the sling is angled more horizontally, the horizontal component of the tension becomes larger. This results in an increase in the overall tension within the sling while the load's effective capacity remains the same. Therefore, the sling is subjected to greater forces, leading to the conclusion that changing to a 30° angle introduces more tension in the sling.

Additionally, while the capacity of the sling itself (its ability to safely lift a load) does not directly decrease, the increased tension can lead to potential overloading if the sling is not rated for the extra stress caused by the lower angle. Thus, the choice correctly identifies that a 30° angle increases tension and implies that it could result in a reduction in effective lifting capacity if the sling were to become overloaded.