How come 7,271,000 mm^3 is equivalent to 7,271 cm^3 ?

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The discussion clarifies the conversion between cubic millimeters (mm^3) and cubic centimeters (cm^3), establishing that 7,271,000 mm^3 is equivalent to 7,271 cm^3 due to the relationship that 1 cm^3 equals 1,000 mm^3. Participants noted that converting from mm to cm involves moving back two decimal places, as 10 mm equals 1 cm. The conversation also highlighted the importance of using unambiguous terminology, such as "cubic centimeters," to avoid confusion with phrases like "centimeters cubed." Misunderstandings about volumetric units and their notation were addressed, emphasizing clarity in mathematical expressions. Overall, the thread served as a learning opportunity regarding metric conversions and proper unit usage.
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Homework Statement
mm to cm
Relevant Equations
7271000mm3 or 7271cm3)
how come 7271000mm3 is equivalent to 7271cm3) ?

from mm to cm you should go back two zeros back right ?
 
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No ! 10 mm = 1 cm

milli from mille, 1000
centi from centum, 100
 
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What is a ##mm##? What is a ##cm##? What is a ##mm^3##? What is a ##cm^3##?
 
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From: https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.330-2019.pdf page 23:
1598790058687.png
 
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BvU said:
No ! 10 mm = 1 cm

milli from mille, 1000
centi from centum, 100

I Didin t realize that
 
PeroK said:
What is a ##mm##? What is a ##cm##? What is a ##mm^3##? What is a ##cm^3##?

so if it was nt cubed I was right then ?
 
chriscarson said:
so if it was nt cubed I was right then ?
I'm afraid not.
:frown:
 
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PeroK said:
I'm afraid not.
:frown:

ok so that s not the difference
 
1 cm3 = 1 cm * 1 cm * 1 cm = 10 mm * 10 mm * 10 mm

elementary school stuff in developed (metricated) countries :smile:
 
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  • #10
BvU said:
1 cm3 = 1 cm * 1 cm * 1 cm = 10 mm * 10 mm * 10 mm

elementary school stuff in developed (metricated) countries :smile:

so 1 cm3 is equal to 1000mm3
 
  • #11
Bingo !
 
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  • #12
BvU said:
Bingo !

It s new to me till now i only made for example 5000 mm is 500 cm , that s why i said you go back just one zero back ,
 
  • #13
Did you say that ? I read
chriscarson said:
from mm to cm you should go back two zeros back right ?
🤔
 
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  • #14
BvU said:
Did you say that ? I read
🤔

yeah i was wrong there
 
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  • #15
All clear now ?
 
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  • #16
yes thank you for your time .
 
  • #18
PeroK said:
To quote Steely Dan: the things that pass for knowldege I can't understand.

oh a book for help , thanks again
 
  • #19
I usually do them like this ##7271000[mm]^3=7271000[10^{-1}cm]^3=7271000\times10^{-3}[cm]^3=7271[cm]^3##
 
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  • #20
There is a benefit for saying volumetric units like "cubic centimetres" instead of "centimetres cubed". The former is unambiguous: $$\text{cubic centimetres} = (\text{cm})^3 = (10^{-2}\text{m})^3 = 10^{-6}\text{m}^3$$whilst the latter could be interpreted in two different ways:$$(\text{centimetres}) \, \text{cubed} = (\text{cm})^{3} = (10^{-2}\text{m})^3 = 10^{-6}\text{m}^3$$ $$\text{centi} \, (\text{metres cubed}) = 10^{-2} (\text{m}^3) = 10^{-2} \text{m}^3$$The former is what is always meant whenever someone says "centimetres cubed", but the wording can be ambiguous. In other words, the English language is not associative :wink:
 
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  • #21
etotheipi said:
There is a benefit for saying volumetric units like "cubic centimetres" instead of "centimetres cubed". The former is unambiguous: $$\text{cubic centimetres} = (\text{cm})^3 = (10^{-2}\text{m})^3 = 10^{-6}\text{m}^3$$whilst the latter could be interpreted in two different ways:$$(\text{centimetres}) \, \text{cubed} = (\text{cm})^{3} = (10^{-2}\text{m})^3 = 10^{-6}\text{m}^3$$ $$\text{centi} \, (\text{metres cubed}) = 10^{-2} (\text{m}^3) = 10^{-2} \text{m}^3$$The former is what is always meant whenever someone says "centimetres cubed", but the wording can be ambiguous. In other words, the English language is not associative :wink:
And here I thought you were going to head for ( 7271 centimeters ) cubed versus 7271 ( centimeters cubed ). The former evaluates to 3.84 x 1011 cubic centimeters and is the preferred meaning. The later is, of course, 7271 cubic centimeters.
 
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  • #22
jbriggs444 said:
And here I thought you were going to head for ( 7271 centimeters ) cubed versus 7271 ( centimeters cubed ). The former evaluates to 3.84 x 1011 cubic centimeters and is the preferred meaning. The later is, of course, 7271 cubic centimeters.

Yeah, there's that too! You have to worry about ##x\,(\text{cm})^3## vs ##x\, \text{c}(\text{m}^3) ## vs ##(x\, \text{cm})^3##! What a mess! So much better to just say ##x## cubic centimetres, ##x\,(\text{cm})^3##.
 
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  • #23
chriscarson said:
so 1 cm3 is equal to 1000mm3
In similar way, 1 ##dm^3## equals 1000 ##cm^3##.
For that reason, liters (##dm^3##) are frequently used for quantifying the displacement of engines rather than cubic centimeters (c.c.).
Example: General Motors engine LS7 is a 7,011 c.c. (7.0 L; 427.8 cu in) engine.
 
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  • #24
Too complicated for me the rest of the comments but thank you all any way.
 
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