How Does Toughness Compare Between Brittle and Elastic Materials?

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The discussion centers on the definitions and comparisons of toughness, brittleness, and elasticity in materials, specifically using a beef burger and a tooth wrenching as examples. Participants clarify that toughness refers to a material's ability to absorb energy and undergo plastic deformation, while brittleness is characterized by a material breaking with minimal deformation. The beef burger is debated as being tough rather than brittle, with some arguing it can be hard but not necessarily brittle unless frozen. The tooth wrenching is described as elastic, potentially tough, but not in the same way as the beef burger. The conversation also touches on the need for clarity regarding the "Salter's syllabus" and its definitions of these material properties.
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Homework Statement
solid properties
Relevant Equations
Tension=Force/Area
stress strain graph
compressive force
UTS
tough and elastic materials
I need some help with the question that I have attached.
I think I should say that the beef burger is tough and brittle but the tooth wrenching is not tough but it's elastic .
or maybe it's tough and elastic.
basically the beef won't have plastic deformation but the tooth wrenching has.
generally I'm not sure how to answer the question.
I appreciate your help.
 

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shk said:
I think I should say that the beef burger is tough and brittle but the tooth wrenching is not tough but it's elastic .
What does "tough" mean in a physics context?
What does "brittle" mean in a physics context?
What does "elastic" mean in a physics context?

Before we can ask whether a beef burger fits those adjectives, we need to know what those adjectives mean.
 
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jbriggs444 said:
What does "tough" mean in a physics context?
What does "brittle" mean in a physics context?
What does "elastic" mean in a physics context?

Before we can ask whether a beef burger fits those adjectives, we need to know what those adjectives mean.

Thanknyou for the reply.
This is what I know :
Elastic material is what returns to it's original shape after reloading..

Brittle material is a material that breaks with a small elastic deformation and almost no plastic deformation. It can be strong or weak.

A tough material is a strong and ductile material. I mean it's something eith great breaking strain and large plastic deformation. The way that the area under the strain stress graph is big.

Hope this was all that you wanted me to say.
I look forward to your help.
Thanks
 
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shk said:
Thanknyou for the reply.
This is what I know :
Elastic material is what returns to it's original shape after reloading..

Brittle material is a material that breaks with a small elastic deformation and almost no plastic deformation. It can be strong or weak.

A tough material is a strong and ductile material. I mean it's something eith great breaking strain and large plastic deformation. The way that the area under the strain stress graph is big.

Hope this was all that you wanted me to say.
I look forward to your help.
Thanks
You have said that you think that a beef burger is brittle. Yet in my experience the only ones I've seen shatter when struck have been frozen. Even those don't shatter well.
 
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jbriggs444 said:
You have said that you think that a beef burger is brittle. Yet in my experience the only ones I've seen shatter when struck have been frozen. Even those don't shatter well.
Thank you.
Ok then so beef burger isn't brittle. It's tough . Can I add any other words for beef burger ? Can I say it's hard ?
how about the other one . Was it correct?
 
The impact strength is the specific work and has a dimension of KGM / cm2. The impact strength depends on the structural state of the steel (for example, on the grain size) and is a very good indicator of the quality of the material.
 
The question only seems to ask about toughness, not about brittleness, elasticity or plasticity. However:
shk said:
the tooth wrenching is not tough but it's elastic .
or maybe it's tough and elastic.
If it's not tough, why was it so hard to bite through?
Does it spring back into shape if released?
shk said:
the beef burger is tough and brittle
Hard to answer this because there are two materials involved and they behave differently.
We are told the bread falls apart, suggesting a degree of brittleness.
The beef is barely affected, implying both hardness and toughness. It tells us nothing of the brittleness, plasticity or elasticity.

jbriggs444 said:
Yet in my experience the only ones I've seen shatter when struck have been frozen.
That would be both hard and brittle. Soft, weak and brittle is also possible.

The style of the question suggests to me that the "correct" answer will be that one or other or both is not tough. Not sure I'd agree.
 
The question is to "explain carefully which food is tough in the Salter's syllabus sense." I googled "Salter's syllabus", keeping "sense" out, but the results made no sense and were unsatisfactory considering the question asked. A search on "Salter's scale" was just as fruitless. Can @shk clarify what this scale is or where it can be found?
 
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kuruman said:
The question is to "explain carefully which food is tough in the Salter's syllabus sense." I googled "Salter's syllabus", keeping "sense" out, but the results made no sense and were unsatisfactory considering the question asked. A search on "Salter's scale" was just as fruitless. Can @shk clarify what this scale is or where it can be found?
My assumption is that the Salter reference defines these properties as in post #3. But of course, there is no absolute definition of any of them, so the question should be whether the foodstuffs are tougher or less tough than some specified material.
 
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semenka said:
The impact strength is the specific work and has a dimension of KGM / cm2.
What are you trying to list as the units? What is a "KGM"?

It looks like the standard unit for Impact Strength is: $$\frac{kJ}{m^2}$$
https://www.intertek.com/polymers/testlopedia/notched-izod-impact-astm-d256/
ISO impact strength is expressed in kJ/m2. Impact strength is calculated by dividing impact energy in J by the area under the notch. The test result is typically the average of 10 specimens.
 
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