Question

The U% of Single yarn is 17.3%. The expected U% of a 3 - ply yarn produced from this yarn will be

• A. 5.8%
• B. 10.0%
• C. 12.3%
• D. 17.3%

Hint:

Plying improves yarn evenness (reduces U%). The U% of the plied yarn is approximately equal to the U% of the single yarn divided by the square root of the number of plies.

Answer 1

The Correct Option is B

Step 1: Effect of Plying on Evenness: Plying (twisting together multiple single yarns) generally improves yarn evenness. This is because variations in the individual single yarns tend to average out. 
Step 2: Formula for U% Improvement: The expected U% of a plied yarn can be estimated using the following formula:

\(U\%\)\(_{\text{plied}}\) =\( \frac{\text{U\%}_{\text{single}}}{\sqrt{n}}\)
where \( n \) is the number of plies (in this case, 3). 
 

Step 3: Calculation: \[ \text{U\%}_{\text{plied}} = \frac{17.3\%}{\sqrt{3}} \approx \frac{17.3\%}{1.732} \approx 10.0\% \]