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https://doi.org/10.1038/s42005-025-02087-0
Challenging common notions on how eggs
break and the role of strength versus
toughness
Check for updates
Antony Sutanto
1,5
, Suhib Abu-Qbeitah
2,3,5
, Avishai Jeselsohn
4
, Brendan M. Unikewicz
4
,
Joseph E. Bonavia
4
, Stephen Rudolph
1
, Hudson Borja da Rocha
1
, S. Kiana Naghibzadeh
1
&
Tal Cohen
1,4
One experiment commonly used to teach young students about the response of structures to dynamic
loading is the egg drop challenge, in which students design a device to protect an egg from cracking
after a fall from a specied height. Relevant to this activity is the choice of orientation of the egg to
decrease the probability of fracture. In this study, we contest the commonly held belief that an egg is
strongest when dropped vertically on its end. Through hundreds of experiments and a set of static and
dynamic simulations, we demonstrate a statistically signicant decrease in the likelihood that an egg
breaks when oriented horizontally as opposed to vertically, and offer a concrete and intuitive
explanation as to why this is the case. These results and the associated analysis demonstrate the
importance of specicity of language and the dangers of appealing to common sense in the physics
classroom while having wide-ranging implications due to the ubiquity of shell structures in nature and
in the man-made world.
In Jonathan SwiftsGulliversTravels
1
, the empires of Lilliput and Blefuscu
engage in quarrels over the optimal orientation to crack an eg g. The ideas,
hardened by centuries of commitment and generations of repetition, gave
rise to an independent conventional wisdom in either society. In our own
society, there exists a similar common sense idea about the best orienta-
tionfordroppinganegg.
Such ideas about the strength of shells have implications beyond the
chicken egg. In nature, shell structures are ubiquitous, serv ing as a protecti ve
layers for soft-bodied organisms; turtle shells and sea shells
2
,tohuman
skulls, and even the outer membranes of viruses and bacteria
3
. Insights on
the mechanical failure of these structures may thus enable progress in a
myriad of applications ranging from the design of protective equipment to
drug delivery
4
.
For this reason, in science classrooms worldwide, the egg drop challenge
is used by educators to introduce young students to the basic ideas of
structural mechanics and impact and to develop their physics intuition
5
.In
this challenge, teams are given materials like cotton balls, plastic bags, and
straws to design a device that prevents an egg from cracking when dropped
from a specied height. A review of instructional materials from various
STEM institutions
6,7
and online tutorials
811
(see Supplementary Table S1)
revealsthatwhilefactorssuchasthematerialsprovided,thedropheight,
and the design solutions vary widely, one aspect remains largely unques-
tioned: the idea that an egg is stronger when oriented vertically as opposed
to horizontally (as illustrated in Fig. 1), and therefore less likely to break. This
idea appears to be based on an appeal to common wisdom, often inspired by
the enduring design of structural arches and domes from ancient
civilizations
12,13
to the present day
1418
. Similar to the shape of a hanging
chainan observation famously captured by Robert Hooke
19
in 1675 with
the aphorism, As hangs the chain, so stands the arch”—under static
loading, a steep arch effectively transmits vertical loads along its curve
(Fig. 1a), eliminating perpendicular forces and taking advantage of the
strong direction of the structure. It may thus seem obvious that this notion
would apply also to the structure of an egg, but is it true?
In this work, by cracking over 200 eggs in total, and employing
high-precision instrumentation to record their respon se in both static and
dynamic conditions, along with predictive numerical simulations,
we answer this question. Through our static tests, we nd that the peak
force required to break an egg is independent of orientation, but due to the
decreased stiffness in the horizontal orientation, an egg can absorb more
kinetic energy before failure. These results are veried through a series of
1
Department of Civil and Environ mental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
2
School of Mathematical & Statistical
Sciences, University of Galway, Galway, Ireland.
3
School of Mechanical Engineering, Tel Aviv University, Tel Aviv, Israel.
4
Department of Mechanical Engineering,
Massachusetts Institute of Technology, Cambridge, MA, USA.
5
These authors contributed equally: Antony Sutanto, Suhib Abu-Qbeitah.
e-mail: hudsonbr@mit.edu; kiana@mit.edu; talco@mit.edu
Communications Physics | (2025) 8:182 1
1234567890():,;
1234567890():,;
drop-tests, which show a decreased likelihood of fracture in the horizontal
orientation, and through a series of static and dynamic numerical simula-
tions of a simple egg structure.
Results and discussion
Peak force is independent of orientation
The ability of an egg to withstand static loads can provide insights into its
ability to resist impact. Hence, as a rst step, we conducted 60 compression
tests to determine whether positioning an egg horizontally or vertically (as
illustrated in Fig. 1b) affects the maximum force it can withstand before
cracking (experimental details are described in Methods section). In each
test, we place an egg on the bottom platen of a universal mechanical testing
machine, stabilized by a paper support. We then control the displacement of
the top platen, compressing the egg, while simultaneously recording the force.
As seen in Fig. 1c, the force-displacement response increases linearly until the
onset of fracture where a peak force is recorded along with the corresponding
displacement, at which a sudden transition to brittle fracture is observed as
the force drops sharply. Surprisingly, regardless of how the eggs are placed,
the peak forces are found to be similar: around 46.0 ± 6.61 N ("mean-value ±
standard-devi ation) for the vertical and 45.2 ± 5.52 N for the horizontal.
To validate these results and determine the mechanisms which explain
the results in Fig. 1, we developed a three-dimensional mechanical model of
aneggthataccountsfortheshellandaviscousliquidyolk.Forsimplicity,we
refer to the entire contents of the egg (both the yolk and albumen) as the
yolk from here on. We further model the shell as a linearly elastic material
with a brittle fracture response. Elastic properties of the egg are obtained
fromtheliterature(seeMethods ). We note that the simplied model in
this work is not intended to capture all of the ensuing physics or to repro-
duce the exact fracture patterns, but instead to identify the essential struc-
tural mechanisms that explain our observations.
To examine if the experimentally observed differences between vertical
and horizontal orientations are captured also in our purely mechanical
model, we calibrate the fracture parameters based on the averaged response
from the vertical compression tests (details on the simulation and material
parameters are provided in Methods section). The simulation for the
horizontal orientation is then conducted using the same material para-
meters. As shown in Fig. 1(d) the simulation predicts the same qualitative
trend as the experiments; the peak force is indistinguishable for the different
egg orientations, and the egg is more compliant when placed horizontally.
These results challenge the common belief that eggs are stronger when
loaded vertically. However, the question remains: what determines the best
orientation to drop an egg?
Eggs are tougher when loaded on their equator
Though we nd that the maximum force an egg can sustain, F,is
independent of its orientation, the displacement of the egg at the onset
of cracking, Δ, varies signicantly (Fig. 1c, d). We nd that eggs loa-
ded horizontally exhibit ~ 30% greater displacement upon cracking
(0.213 ± 0.022 mm) compared to eggs loaded vertically (0.161 ± 0.015 mm).
Namely, the stiffness of the egg, dened as k = F/Δ,issmallerinthehor-
izontal direction. Since the peak force is independent of orientation, this
implies that the loading orientation inuences the level of energy absorption,
which is equivalent to the area under the force-displacement curves up to the
point of fracture, i.e., E = FΔ/2, assuming linear dependence between
compressive force and displacement. Accordingly, on average, eggs loaded
horizontally can absorb ~ 30 % more energy before failure. Notice that the
distribution of the experimentally measured energy absorption, shown in
Fig. 1e, exhibits a statistically signicant difference with normal statistical
distribution for 30 tests in each loading direction, thus further supporting the
observation that eggs loaded horizontally can absorb more energy before
Fig. 1 | Static compression. a The eggs load bearing capabilities are often described
in analogy to those of structural arches, which effectively redistribute loads
29
. In this
work, we investigate just how valid this analogy is. b Eggs are statically loaded in two
orientations: vertically (red, top) and horizontally (blue, bottom). The experimental
crack patterns are shown in the second column. For improved visualization, the
crack lines in the vertical orientation are enhanced. The right two columns display
similar crack patterns obtained from numerical simulations. c Experimental force-
displacement curves. Thin lines represent individual tests, while thick lines show the
average curves for each orientation. The continuous regions of the curves before and
after cracking are averaged separately. d Simulated force-displacement curves.
e Violin plot of the energy absorbed before cracking. The plot displays the median,
interquartile range, and the distribution of data points. There is a statistically sig-
nicant difference between the absorbed energy for different orientations
(p < 0.0001).
https://doi.org/10.1038/s42005-025-02087-0 Article
Communications Physics | (2025) 8:182 2
cracking. Dening the toughness of an egg as the amount of energy it can
absorb before failure, we can thus conclude that based on our results eggs are
tougher when loaded horizontally.
Crack patterns are another notable difference observed between ver-
tically and horizontally loaded eggs. As seen from both the experiments and
the numerical model (Fig. 1b), horizontal compression typically results in
cracks that propagate along the equator of the egg thus splitting it open,
while vertical compression often leads to cracks that propagate in a spiral
pattern from the contact point of the blunt end leading to shell caving.
While various material and geometric factors may contribute to the
overall toughness of an egg, our simplied model that considers an isotropic
shell of uniform thickness can capture the observed trends in both the force-
displacement responses and the fracture patterns. This strengthens the
assumption that these minimal mechanical considerations are sufcient and
that other mechanisms play a secondary role in determining the eggs
toughness. Furthermore, it re-enforces the overall conclusion that eggs are
tougher when loaded on their equator.
Dynamic drop tests corroborate static results
It remains to be seen if the static toughness of an egg can predict its ability to
withstand a drop. To this end, we conducted a series of drop tests. Using
solenoid-based supports mounted on a universal mechanical testing
machine (see Methods), eggs were dropped from various heights onto a
xed support that is connected to a force sensor (Fig. 2a). An indication of
cracking can be seen from a drop in the measured force-time response, and
conrmed via visual inspection (see Supplementary Fig. S2). Following a
series of initial tests dedicated to identifying the range of relevant drop
heights for different orientations, we performed 60 tests for each orientation;
20 for each of the three different heights, 8, 9, and 10 mm, as shown
in Fig. 2b.
Note that, in contrast to static compression, for the dynamic tests we
distinguish between impact on the blunt and sharp ends, in the vertical
conguration. In both the static and dynamic loading cases, placing the egg
with its blunt or sharp end down in the vertical orientation does not change
the results. However, during the static tests, fracture consistently occurs on
the sharp side of the egg, regardless of the vertical orientation, shedding
some light on the intricacies and nuance involved in the seemingly eternal
conict between the kingdoms of Lilliput and Blefuscu.
While no statistically signicant difference is observed in comparing
results for eggs dropped in either of the vertical orientations, a clear dif-
ference is seen when comparing the vertical and horizontal congurations.
The number of eggs that cracked when impacted on their equato r was lower
than those impacted on their poles. Namely, these results suggest that an egg
dropped on its equator can likely sustain greater drop heights without
cracking.
Similar to the sta tic tests, mechanical analysis is sufcient to explain
and predict the result of the drop test. Using the same material properties
and modeling framework as developed and calibrated for the static case, we
conduct numerical simulations to obtain the force versus time responses for
eggs dropped from different heights (Fig. 3). As conrmed by examining the
failure criteria in the simulation, curveswithsharpdropsinforceindicate
cases where the egg cracks upon impact, while smooth curves indicate cases
where the egg deforms elastically and thus recovers by bouncing back after
engaging with the support
20
.Notably,fractureisrst observed when eggs are
dropped from a height of 8.6 mm for the vertical orientation. Orienting the
egg along its equator allowed it to reach 0.3 mm higher than in the vertical
Fig. 2 | Dynamic drop experiments. a Sequence of experimental snapshots for
vertical (top) and horizontal (bottom) drops. b Percentage of eggs cracked when
dropped from three different heights in various orientations. Corresponding force-
time curves are provided in Supplementary Fig. S7 and on Github
20
. Corresponding
videos are found in Supplementary Movie 1.
Fig. 3 | Dynamic drop simulations. Force-time curves for egg drops from various
heights in vertical (top) and horizontal (bottom) orientations. Curves with sharp
drops represent cracking.
https://doi.org/10.1038/s42005-025-02087-0 Article
Communications Physics | (2025) 8:182 3
orientation without cracking, conrming a real albeit small advantage of
dropping the egg along its equator.
Examining the curves for the intact eggs in Fig. 3 we nd that the
contact time with the platen (i.e., the extent of time in which the force
measurement is non-negative), is larger for the horizontal orientation. This
result suggests that the egg is more compliant in this conguration, also for
the case of dynamic impact, thus corroborating the prediction based on egg
toughness. This increased compliance is most likely attributed to the eggs
structure, given that the same material properties are used in both orien-
tations. This inuence of geometry is also reected in the fracture patterns
that em erge and the corresponding stress distribution (see Supplementary
Fig. S3). Nonetheless, in all three orientations, the cracks originate from the
point of contact and propagate outwards as seen from both the experiments
and the simulations. To numerically investigate the initiation of cracking,
the material properties of the egg are calibrated based on the static experi-
mental results and can thus be considered as equivalent material properties
for the shell with the internal membrane. The simulations are able to
illustrate the dynamic cracking even for higher drops (see Supplemen-
tary Fig. S4).
Conclusions
The presented results support the idea that an egg is less likely to crack when
dropped on its equator. This result is contrary to the conventional wisdom
that an egg is stronger in the vertical direction. So what went wrong?
Tounderstandthiswecanexaminethecommonstepsinlogicmadeby
popular science communicators and institutions on the strength of an egg.
Below is a set of basic descriptions of the common arguments found in
popular science media (see Supplem entary Table S1), and an analysis of
their validity, based on our experiments and simulations. These are not exact
quotes but represent common threads in explanation among the examined
sources.
Eggs are stiffer when loaded in the vertical direction.
This is true. Both our experiments and our numerical simulations
verify that the stiffness k ofaneggishigherwhenloadedinthevertical
direction.
This means that eggs can sustain more force when loaded in the vertical
direction.
Even conceptually, this is not necessarily true. The peak force F may
depend on a number of material and geometric factors, which are inde-
pendent of the stiffness. For instance, the stiffness of a column is determined
by its cross-sectional area, but the force at which it buckles is determined by
its area moment of inertia. Therefore, a column with a larger area, but
smaller moment of inertia will be stiffer but attain a lower peak force
21
.Inour
experiments, we found no statistical difference between the peak force in the
vertical and horizontal directions, consistent with our numerical
simulations.
Because an egg can sustain a higher force in the vertical direction, it is
less likely to fracture during impact.
This is incorrect. Even if eggs could sustain a higher force when loaded
in the vertical direction, it does not necessarily imply that they are less likely
to break when dropped in that orientation. In contrast to static loading, to
remain intact following a dynamic impact, a body must be able to absorb all
of its kinetic energy by transferring it into reversible deformation. For an egg,
assuming a linear force-displacement relationship (supported by the data in
Fig. 1c, d), we can write the total energy absorption (i.e., the egg toughness)
and kinetic energy, K at impact as
E ¼ F
2
=ð2kÞ; K ¼ mgh
respectively, g refers to the acceleration due to gravity. With K and F
independent of orientation, and given that k is higher for an egg loaded in
the vertical direction, one should expect that E ishigherforaneggwhen
loaded in the horizontal orientation; it would thus be less likely to break
when impacted on its equator and experiencing lower force. This is in
agreement with the results of our dynamic experiments and simulations.
It is evident now that the awinthecommonargumentiswiththe
denition of a strong egg, [see Supplementary Table S17]. The pre-
ponderance of STEM communicators understand that an egg is stiffer in one
direction, but they equate this with strength in all other senses. However,
eggs need to be tough, not stiff, in order to survive a fall. We understand this
intuitively. When we fall we know to bend our knees rather than lock them
straight, which could lead to injury. In a sense, our legs are weaker,ormore
compliant, when bent, but are tougher, and therefore stronger during
impact, experiencing a lower force over a longer distance.
Our results and analysis serve as a cautionary tale about how language
can affect our understanding of a system, and improper framing of a pro-
blem can lead to misunderstanding and miseducation. We hope that this
revised framing of the problem will help equip budding scientists and
engineers with a better understanding of the way in which objects and
structures react to impact and dynamic loads.
Methods
Egg selection and measurement
We purchased USDA Grade AA Cage Free Large Eggs in cartons of 60 eggs
from Costco under the Kirkland Signature brand. Prior to testing, eggs were
allowed to reach room temperature. We inspected eggs for any potential
defects. If we determined the presence of a pre-existing crack (through a
visual inspection for hairline cracks on the shell), we discarded the egg and
did not include it in subsequent testing. Of the eggs tested, properties that we
recorded to inform nite element simulation were length, L,dened as the
distance in the long-axis direction from the sharp end to the blunt end;
width, B,dened as the maximum diameter of the egg perpendicular to the
long-axis, and mass, m. We measured the lengths via a TOL-10997 Digital
Caliper with accuracy of ±0.02 mm. Thickness of the eggshell, t,was
measured using a Mitutoyo Digital Micrometer H-2780 with accuracy of
±0.001 mm. Mass was measured using a Bonvoisin laboratory scale with
accuracy of ±0.01 g. We calculated the average length to be 56 mm, the
average width to be 44mm, and the average mass to be 59 g.
Physical experiments
We used an Instron 5943 universal testing machine to measure force in both
the static and dynamic tests, and for controlling the displacement in the
static tests. The precision in tracking the displacement is ±0.01mm, and the
resolution for the load measurement is ±0.05N.
Static compression tests. For testing, we rested a single egg on a xed
platen and then compressed it by moving the top platen, which was
connected to the 1kN load cell. We oriented the eggs in one of two
directions, vertical or horizontal. To ensure correct alignment of the egg
with the center of the moving platen, specially designed supports were
constructed from letter-size copy paper as shown in Supplementary
Fig. S1. We found that increasing friction between the egg and platen
during testing did not alter the central conclusions of our original
experiments, as can be seen in Supplementary Fig. S10. When testing, the
BlueHill software recorded reaction forces, time, and displacement of the
moving platen, at 10 mm/min, into the egg up to and past cracking. Data
collected from the tests is provided in Supplementary Note 2.
Drop tests. Opposite the static compression tests, we xed the 1kN load
cell to the bottom platen and the Bluehill software was congured to
record the force at a sampling rate of 1 kHz. To consistently drop the eggs
at the correct orientation with minimal rotation, we 3D printed a
solenoid-based device out of Polylactic acid (PLA). With no top platen,
we tted the device into the moving cross-head of the Instron 5943
https://doi.org/10.1038/s42005-025-02087-0 Article
Communications Physics | (2025) 8:182 4
universal testing system. The device holds two UXCELL 0.8N, 10 mm
stroke push-pull electromagnet solenoids, with 3D-printed angled egg
supports to stabilize the egg prior to dropping. To actuate the solenoids,
thereby dropping the egg, we wired both solenoids to a pair of 9V bat-
teries, connected in series, to a Single-Pole Single-Throw (SPST) rocker
switch. Experimental setup is shown in Supplementary Fig. S5.
A drop test is carried out as follows: First, we place the egg atop the
solenoid supports and reset the 1kN load cell such that the force reading is
0.0N. To precisely set the drop height, we use the cross-head of the Instron
system, to lower the device until the egg lightly touches the load cell and the
force reading is 0.1N, indicating rst contact. We then reset the gauge length
extension to zero and translated the egg assembly upwards to heights of 8.0,
9.0, and 10.0 mm for testing. With the egg in place, we begin data collection
and toggle the SPST rocker switch to ON triggering the solenoid arms to
simultaneously retract and release the egg for impact onto the bottom
platen.
We dropped the eggs in three different orientations: horizontal on their
equator, vertical on their sharp end, and vertical on their blunt end. Twenty
eggs were tested per orientation and the drop procedure was repeated at
heights of 8.0mm, 9.0mm, and 10.0mm for a total of 180 eggs tested.
Cracked eggs were identied through analysis of force-time curves recorded
by the Instron system and subsequent visual inspection. A sharp drop in
force was interpreted as a crack event. Conversely, if the egg bounced (as
reected in the force-time plot as a wave with decreasing amplitude) the egg
was likely intact, although some did crack. To ensure accuracy, we visually
inspected all eggs for hairline fractures after a few days. If we detected a
fracture, the egg was classied as cracked. Raw Data from the dynamic tests
can be found in Supplementary Note 3.
Numerical experiments
Full 3D simulations were conducted using the Finite Element Analysis
software, Abaqus/Explicit. We structured the egg with an exterior eggshel l
modeled as a linear elastic material, and an interior yolk modeled as a
viscous uid. The average measured dimensions of the experimental
eggs were used to dene the model egg geometry. For the yolk, we
adopted mass density and viscosity values as reported in the literature
22,23
,
i.e., 1.02 g/cm
3
, and 1322MPa s, respectively. The shel ls Youngsmodulus,
Poissons ratio, and mass density wer e also taken to agree with reported
values
2426
i.e., 49GPa, 0.3, and 2.241 g/cm
3
, respectively. We postulated shell
fracture as brittle failure with material parameters calibrated to match the
average experimental curve for static compression in vertical loading
(Fig. 1): the failure stress as 23MPa, the Mode I fracture energydening
the energy required for failureas 3.728 mJ. The calibrated failure stress
of 23MPa matches closely to the value of 19.9MPa determined from
Liu et al.
27
. Additionally, we simulated the half-shell experiments performed
in Liu et al.
27
and were able to capture the same trends. More details of
these simulations can be found in Supplementary Not e 4. To specify the
post-cracking shear behavior, we dened the shear retention factor-crack
opening strain relationship as crack opening strain of 0 corresponding
to shear retention factor of 1, and crack opening strain of 0.002922
corresponding to shear retention factor of 0. For more information
about the latter parameters, the reader is referred to ABAQUS
documentation
28
.
The eggshell domain was discretized using unstructured S4R elements
with an element size of 2mm with reduced integration and nite membrane
strain. Note that when a crack propagates through an element, the failed
element may experience severe distortion. In this case, it is removed from the
mesh once the damaged criterion is satised. To accommodate this we
enabled element deletion in the ABAQUS element controls. Mesh depen-
dence analysis conrms that the current approach captures the correct
qualitative trends (see Supplementary Fig. S2).
We analysed the interaction between the yolk and the eggshell via the
Coupled Eulerian-Lagrangian (CEL) technique. To specify the exact loca-
tion of the yolk inside the eggshell, we used a predened material assignment
after creating a discrete eldusingthevolumefractiontool.ABAQUStracks
the material ow in each element by using volume fraction, which repre-
sents the percentage of the elementsvolumelled with material at any given
moment. We discretized the yolk domain using a structured mesh of 8-node
brick elements of EC3D8R Eulerian family element type with an element
size of 2 mm. The top and bottom supports are modeled as 3D discrete rigid
plates, which we discretized via unstructured mesh of 4-node 3D bilinear
rigid quadrilateral elements (R3D4).
Static compression tests modeling. To simulate static compression,
we bounded the egg by top and bottom supports. The top support
translates in the vertical direction at a constant velocity, 100 mm/min,
while the bottom support remains stationary. To prevent rotation of the
egg we constrained the top and bottom tips of the egg to move only along
the vertical axis. It is worth mentioning that both 10 mm/min and
100 mm/min velocities were tested experimentally, with no signicant
difference observed in the results. To reduce simulation time, we adopted
the 100 mm/min velocity in our simulations, as using 10 mm/min would
have led to excessively long computational times, which are impractical
for model calibration with the Coupled Eulerian-Lagrangian (CEL)
approach. Simulations were conducted using dynamic explicit stepping
with a time period of 0.35 seconds and geometric nonlinearities were
captured by choosing the NLGEOM option.
Drop tests modeling. To model a dynamic drop, we used the same setup
as for static compression, but without the top support. We dropped the
egg from a prescribed height onto the stationary bottom support. We
adopted the same material parameters, egg dimensions, loads, mesh
types, and number of elements as in the compression tests. We modeled
the egg when it reached a height of 0.5 mm from the oor by prescribing
an initial velocity using energy conservation, v ¼
ffiffiffiffiffiffi
2gh
p
, which matched
the experimental drop values. We use a dynamic explicit step with a time
period of 0.005 s. For smooth tracking of fracture, we dened the output
frequency of intervals as 50.
Data availability
All of the experi mental data is provided in the Supplementary Information
and available online via GitHub (cohen-mechanics-group/nature-comms-
phys-egg).
Received: 24 October 2024; Accepted: 1 April 2025;
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Acknowledgements
We acknowledge the partial support of our work through Ofce of Naval
Research grant N000142312530 and the support from the National Science
Foundation under award number CMMI1942016. S.K.N. acknowledges the
MIT Postdoctoral Fellowship Program for Engineering Excellence (PFPFEE).
J.E.B. acknowledges the support of the NSF GFRP. T.C. would like to
dedicate this work to her PhD advisor, David Durban, on the occasion of his
80th birthday, and to the memory of Neev-ya Durban, the founder of the
Technion Egg Drop competition; an inspiration for this work.
Author contributions
A.S., B.M.U., S.R., H.Bd.R., S.K.M., and T.C. contributed to the
conceptualization and methodology. T.C. provided resources, project
administration, supervision, and funding acquisition. A.S., B.M.U. and
S.K.N. contributed to data curation. A.S., S.A.Q., A.J., B.M.U., J.E.B., and
S.K.N. were responsible for validation, formal analysis, and investigation.
A.J., S.A.Q., H.Bd.R., and S.K.N. contributed to visualization. S.A.Q.
developed the software. Writing, including original draft preparation and
review and editing, was carried out by A.J., S.A.Q., B.M.U., J.E.B., H.bd.R.,
S.K.N., and T.C.
Competing interests
The authors declare no competing interests.
Additional information
Supplementary information The online version contains
supplementary material available at
https://doi.org/10.1038/s42005-025-02087-0
.
Correspondence and requests for materials should be addressed to
Hudson Borja da Rocha, S. Kiana Naghibzadeh or Tal Cohen.
Peer review information Communications Physics thanks DavidTaylor and
the other, anonymous, reviewer(s) for their contribution to the peer review of
this work. [A peer review le is available].
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Communications Physics | (2025) 8:182 6

Discussion

> "One experiment commonly used to teach young students about the response of structures to dynamicloading is the “egg drop challenge”, in which students design a device to protect an egg from crackingafter a fall from a specified height. Relevant to this activity is the choice of orientation of the egg todecrease the probability of fracture. In this study, we contest the commonly held belief that an egg isstrongest when dropped vertically on its end. Through hundreds of experiments and a set of static anddynamic simulations, we demonstrate a statistically significant decrease in the likelihood that an eggbreaks when oriented horizontally as opposed to vertically, and offer a concrete and intuitiveexplanation as to why this is the case. These results and the associated analysis demonstrate theimportance of specificity of language and the dangers of appealing to “common sense” in the physicsclassroom while having wide-ranging implications due to the ubiquity of shell structures in nature andin the man-made world." Gulliver's Travels, by Lemuel Gulliver, is a 1726 prose satire by the Anglo-Irish writer and clergyman Jonathan Swift, satirising human nature. In the book, a major point of contention between the two kingdoms of Lilliput and Blefuscu is how to crack an egg. Blefuscu is described as favoring cracking eggs at the "small end," while Lilliput adheres to the "large end" method. This seemingly trivial difference in food preparation has escalated into a religious and political divide, leading to prolonged conflict and even war between the two nations. For more: https://en.wikipedia.org/wiki/Gulliver%27s_Travels The egg drop challenge is widely used around the world as an engineering/science experiment: fun video going over the challenge-> https://www.youtube.com/watch?v=nsnyl8llfH4 Fun article that provides a nice overview of the paper: https://news.mit.edu/2025/mit-engineering-students-crack-egg-dilemma-sideways-stronger-0508