Final answer:
The correct answer is option 2) Decreases.A knot in a lanyard decreases its overall strength due to localized stress and strain at the knot, with a potential reduction in strength by 20% to 50%.
Step-by-step explanation:
When you tie a knot in a lanyard or any rope, it affects the rope's overall strength. Generally, a knot in a rope will weaken it because the rope's fibers are bent sharply and twisted in a way that causes localized stress and strain points. A tightly drawn knot can reduce a rope's strength significantly because the forces are concentrated at the knot, causing the material to stretch and wear more at these locations than in the straight sections of rope. While the exact amount of strength reduction can vary based on the type of knot and the material of the rope, it is commonly accepted that knots can reduce a rope’s strength by anywhere from 20% to 50%.
A knot in a lanyard decreases its overall strength. When a knot is tied in a lanyard, it creates points of stress concentration, which weakens the structure of the lanyard. These stress points can cause the lanyard to fail under lower loads than if it were knot-free.
For example, imagine a lanyard made of a strong and flexible material like nylon. When a knot is tied in the lanyard, the fibers around the knot are compressed and twisted, creating weak spots that can lead to the lanyard breaking.