How Can You Calculate the Impact Force of a Falling Egg?

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Discussion Overview

The discussion revolves around calculating the impact force of a falling egg, focusing on theoretical approaches rather than empirical measurements. Participants explore the necessary parameters, such as stopping time or distance, and the challenges of estimating these for an egg compared to other objects like a car.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant notes that engineering calculators require known stopping time or distance, which is difficult to estimate for an egg.
  • Another participant emphasizes the need for theoretical calculations without relying on measurements or video analysis.
  • Some participants suggest that the impact force can be derived from the mass of the egg, height dropped, and acceleration due to gravity.
  • There is a discussion about the difficulty of estimating the crumple distance for an egg compared to a car.
  • One participant mentions the formula for calculating force as mass times acceleration and expresses uncertainty about the collision duration needed to determine impact force.
  • A later reply provides a formula for dynamic energy at impact, suggesting a relationship between force, mass, gravity, and height.

Areas of Agreement / Disagreement

Participants do not reach a consensus on how to estimate stopping time or distance for the egg, and multiple competing views on the approach to calculating impact force remain unresolved.

Contextual Notes

Participants highlight limitations in estimating parameters necessary for calculations, such as stopping time and distance, and the assumptions involved in treating the egg as a solid object during impact.

houlahound
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I searched engineering calculators and they rely on the input you know the stopping time or the stopping distance - easy for a car but not an egg.

Knowing either of these quantities makes the problem trivial, but how to estimate or calculate them??

What is the best assumption for either and how is the assumption justified for a free falling egg hitting concrete.

I would like to do it theoretically and not use video or force sensors.

Is this possible?
 
Last edited:
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houlahound said:
I searched engineering calculators ...
If you can't solve a problem without a calculator you should not expect to be able to solve it WITH a calculator.
 
Actually I just looked at how the calculator solved the problem ie what equations. I get the physics given impact time or distance - I have no idea how to get values for time or distance of stopping apart from measurement.

If you can point me in right direction be appreciated.
 
houlahound said:
Actually
Is that single word response supposed to mean something?
 
I have to post a random string then use the edit box to make the text not gibberish...tedious.
 
houlahound said:
I have to post a random string then use the edit box to make the text not gibberish...tedious.
That seems odd. How can you be able to post a string of gibberish but not instead post a real response?
 
Don't know...but back to the question.
 
you have to make some effort yourself...
list the things you know about the egg and its fall
then you can figure out how to find the force that the egg hits the ground with
 
Because a car a crushing distance is easy to estimate eg the crumple distance. Usually qouted around 0.5m.

An egg??
 
  • #10
houlahound said:
Because a car a crushing distance is easy to estimate eg the crumple distance. Usually qouted around 0.5m.

An egg??

forget about the crumple distance at this stage ... let's initially treat it as a solid object

again ...

davenn said:
list the things you know about the egg and its fall
Dave
 
  • #11
Lands at speed root(2gh)
Above some height h egg cracks on impact.
No observable deformation, just catastrophic fracture.

Nothing else I can think of.
 
  • #12
houlahound said:
Nothing else I can think of.

you haven't stated any of the things that need to be considered to work out the force of the impact

here's some hints
mass of the egg,
height dropped from
acceleration rate at the time of impact

what is the formula for working out force of a falling object "in" gravity ?Dave
 
Last edited:
  • #13
All I got from that is;

F=mass of egg x acceleration = mass of egg x velocity / time

Initial acceleration = g

velocity initial = root(2gh)

velocity final = 0

time from when egg hits ground until it stops moving ie collision duration I don't know and what needs to be known to work out impact force.
 
  • #14
try this ...

Impact Force from a Falling Object
The dynamic energy in a falling object at the impact moment when hitting the ground can be calculated as

E = Fw h
= m g h (4)


where

Fw = force due to gravity - weight (N, lbf)

g = acceleration of gravity (9.81 m/s2, 32.17405 ft/s2)

h = falling height (m)

The equation can be combined with the equation of work to:

F = m g h / s

now using that work out the force
 

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