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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

, Brendan M. Unikewicz

Joseph E. Bonavia

, Stephen Rudolph

, Hudson Borja da Rocha

, S. Kiana Naghibzadeh

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 speciﬁed 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 signiﬁcant 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 speciﬁcity 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 Swift’sGulliver’sTravels

, 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

,tohuman

skulls, and even the outer membranes of viruses and bacteria

. 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

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

.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 speciﬁed height. A review of instructional materials from various

STEM institutions

6,7

and online tutorials

8–11

(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

14–18

. Similar to the shape of a hanging

chain—an observation famously captured by Robert Hooke

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 ﬁnd 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 veriﬁed through a series of

Department of Civil and Environ mental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.

School of Mathematical & Statistical

Sciences, University of Galway, Galway, Ireland.

School of Mechanical Engineering, Tel Aviv University, Tel Aviv, Israel.

Department of Mechanical Engineering,

Massachusetts Institute of Technology, Cambridge, MA, USA.

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():,;

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 ﬁrst 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(see“Methods ”). We note that the simpliﬁed 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 ﬁnd 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 signiﬁcantly (Fig. 1c, d). We ﬁnd 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, deﬁned as k = F/Δ,issmallerinthehor-

izontal direction. Since the peak force is independent of orientation, this

implies that the loading orientation inﬂuences 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 signiﬁcant 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

. 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-

niﬁcant 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. Deﬁning 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 simpliﬁed 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 sufﬁcient and

that other mechanisms play a secondary role in determining the egg’s

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

ﬁxed 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

conﬁrmed 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

conﬁguration. 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

conﬂict between the kingdoms of Lilliput and Blefuscu.

While no statistically signiﬁcant 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 conﬁgurations.

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 sufﬁcient 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 conﬁrmed 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

.Notably,fractureisﬁrst 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

. 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, conﬁrming a real albeit small advantage of

dropping the egg along its equator.

Examining the curves for the intact eggs in Fig. 3 we ﬁnd 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 conﬁguration, also for

the case of dynamic impact, thus corroborating the prediction based on egg

toughness. This increased compliance is most likely attributed to the egg’s

structure, given that the same material properties are used in both orien-

tations. This inﬂuence of geometry is also reﬂected 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

.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

=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 ﬂawinthecommonargumentiswiththe

deﬁnition 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 ﬁnite element simulation were length, L,deﬁned as the

distance in the long-axis direction from the sharp end to the blunt end;

width, B,deﬁned 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 ﬁxed

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 ﬁxed the 1kN load

cell to the bottom platen and the Bluehill software was conﬁgured 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 ﬁtted 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 ﬁrst 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 identiﬁed 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

reﬂected 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 classiﬁed 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 ﬂuid. The average measured dimensions of the experimental

eggs were used to deﬁne 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

, and 1322MPa ⋅ s, respectively. The shel ls Young’smodulus,

Poisson’s ratio, and mass density wer e also taken to agree with reported

values

24–26

i.e., 49GPa, 0.3, and 2.241 g/cm

, 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 energy–deﬁning

the energy required for failure–as 3.728 mJ. The calibrated failure stress

of 23MPa matches closely to the value of 19.9MPa determined from

Liu et al.

. Additionally, we simulated the half-shell experiments performed

in Liu et al.

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 deﬁned 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

The eggshell domain was discretized using unstructured S4R elements

with an element size of 2mm with reduced integration and ﬁnite 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 satisﬁed. To accommodate this we

enabled element deletion in the ABAQUS element controls. Mesh depen-

dence analysis conﬁrms 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 predeﬁned material assignment

after creating a discrete ﬁeldusingthevolumefractiontool.ABAQUStracks

the material ﬂow in each element by using volume fraction, which repre-

sents the percentage of the element’svolumeﬁlled 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 signiﬁcant

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 ﬂoor by prescribing

an initial velocity using energy conservation, v ¼

ﬃﬃﬃﬃﬃﬃﬃ

2gh

, 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 deﬁned 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 Ofﬁce 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 ﬁle is available].

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https://doi.org/10.1038/s42005-025-02087-0 Article

Communications Physics | (2025) 8:182 6

> "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

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