Materials Scientist: A new synthetic polymer, Elastium, is being adopted for manufacturing outdoor climbing ropes. Laboratory tests demonstrate that individual Elastium fibers are 30 percent more resistant to physical abrasion than the nylon fibers currently used in standard climbing ropes. Therefore, climbing ropes constructed entirely from Elastium will have a significantly longer safe-usage lifespan than current nylon climbing ropes.
Which of the following are assumptions on which the materials scientist's argument depends? (Select all that apply)
- The increased abrasion resistance of individual Elastium fibers results in a corresponding increase in the abrasion resistance of ropes woven from those fibers.Answer
- Elastium ropes do not degrade from other environmental factors, such as ultraviolet exposure, much more rapidly than nylon ropes do.Answer
- CPhysical abrasion is the only factor that dictates the safe-usage lifespan of a climbing rope.
- DThe manufacturing process for Elastium climbing ropes is no more expensive than the process for nylon ropes.
- ECurrent nylon climbing ropes frequently fail to meet the minimum safety standards required for outdoor climbing.
Answer
The correct options are the one stating that individual fiber resistance transfers to the woven rope, and the one stating Elastium does not degrade much more rapidly from other environmental factors.
The argument relies on two distinct assumptions. First, it assumes a part-to-whole relationship: that the superior abrasion resistance of individual Elastium fibers actually translates into superior abrasion resistance for the entire woven rope. If it does not, the conclusion fails. Second, it assumes that Elastium does not suffer from a separate, unstated vulnerability (such as rapid UV degradation) that would offset its superior abrasion resistance and shorten its overall safe-usage lifespan. Both of these unstated premises must be true for the conclusion to remain logically viable.
Step-by-Step Solution
Key Concept
Necessary Assumption