Question

summarizing informational text quick check
\science: why shoelace knot failure\
by nolan alpan
no matter how tight you tug, it feels like some shoelaces are doomed to come untied. not any longer, as new research from the university of california, berkeley, has figured out the physics behind why the knots fail and why some shoelaces are more prone to the mistake.
while the poetic inevitability of the slip - up may provide comfort to those afflicted by wayward shoelaces, the research published tuesday in the proceedings of the royal society of london a may also provide clues for building soft - robotic robots.
mechanical engineer oliver oreilly began looking into this little problem three years ago, after trying to teach his young daughter to tie her shoes.
i went online and found all these beautiful videos about how to tie your shoelaces, oreilly said. they were wonderful and very helpful, but i also noticed there were no videos online about why your shoelaces become untied.
the dearth of information piqued oreillys attention because he studies dynamics - the science of motion - at graduate - student and post - doc levels. while disneys big hero 6 might look cool on the big screen, a lot of mathematical models on materials and how materials deform would be needed to build such a robot. so oreilly handed off this investigation into shoelaces as a class project for two of his graduate students, christopher daily - dixon and chloe gregg.
right off the bat, they found anomalies didnt exist when just picking new foot or when they only changed the gravity. the combination of the two main activities - walking and running - appeared important.
the team acquired a high - speed camera and positioned it at greggs shoes as she ran on a treadmill. gregg had tied her shoes with one of two knots: square (strong) knot or a granny (weak) knot. then they saw how oreilly described the difference between the two.
you tie the laces first. thats where you loop the strands together, one around the other. next, you form the \bunny ears\. if you keep the bunny knots together the same direction that you tied the first knot together, thats a strong knot. but if you do the opposite, instead of putting one over the other, you switch the order, then you get the weak knot.
youd think the reason why nothing happened for a long time, and then - all of the sudden - the laces came untied, was simply due to the looseness of the knot. it cant merely be a loose knot or a weak knot.
to answer questions about the physics of the phenomenon, the new research adhered a small device to the end of the laces, the accelerometer, and gregg ran for a while at 4 mph. this is disney - meets - science - fiction, when the laces are moving, the accelerometer is sending data to a computer.
use the passage to answer the question.
drag each sentence into the correct order to accurately summarize the text
(2 points)

• research showed that a single kind of motion did not cause shoelaces to come untied.
• it is a combination of the two main movements used in walking that leads to shoelace knot failure.
• two graduate students began to study the effects of motion on shoelace knots.
• a researcher wondered about the science behind shoelaces coming untied.

Explanation:

The passage starts with a researcher's curiosity about shoelace knot - failure. Then two graduate students were involved in the study. Research showed single - motion didn't cause untying, and it's a combination of walking motions that does.

Answer:

1. A researcher wondered about the science behind shoelaces coming untied.
2. Two graduate students began to study the effects of motion on shoelace knots.
3. Research showed that a single kind of motion did not cause shoelaces to come untied.
4. It is a combination of the two main movements used in walking that leads to shoelace knot failure.