Posted: Sat Oct 28, 2006 3:20 pm
**********************************************************
UNITS:
The Units for Youngs Modulus should be 'Pascals' abbrieviated to 'Pa'
a Pascal is the same as Newtons/Meter^2 (or N/m^2)
You will often find it quoted as MPa (Megapascals) or GPa(Gigapascals)
1 MPa = 1,000,000 Pa
1 GPa = 1,000,000,000 Pa
**********************************************************
TYPICAL VALUES:
On wikipedia typical values for youngs modulus are:
Steel 200 GPa (200 E9 Pa, or 200 X10^9Pa)
Typical Wood 10 GPa (10 E9 Pa, or 10 X10^9Pa)
Glass 72 GPa (72 E9 Pa, or 72 X10^9Pa)
so for Typical Wood that is:
10,000,000,000 Pa as it is in the spreadsheet I believe.
**********************************************************
CONVERSION FROM TABLE ON THIS SITE:
The data in the Kams table is a bit wierd:
The units for youngs modulus should be force / area. The units in the table are in mass / area which is not a valid unit for youngs modulus really. For the conversion I have assumed that 1Kg is equivalent to 10N (this is a commonly used conversion although only valid on earth), so we have:
Table value = 1000Kg/mm^2
=10,000 N/mm^2
=10,000,000,000 N/m^2 (Pa)
This matches the value from Wikipedia so I would assume that you can take the data in the spreadsheet and multiply by 10,000,000 and you have the youngs modulus in Pa which are the units in the spreadsheet.
Like I said the units in the table are a bit wierd because they would imply that the material stiffness would change depending on gravity (which is not true), but this kind of missunderstanding of the difference between mass and force is common so I am 95% sure that the conversion that I have done is correct.
I hope that answers all your questions.
B.
UNITS:
The Units for Youngs Modulus should be 'Pascals' abbrieviated to 'Pa'
a Pascal is the same as Newtons/Meter^2 (or N/m^2)
You will often find it quoted as MPa (Megapascals) or GPa(Gigapascals)
1 MPa = 1,000,000 Pa
1 GPa = 1,000,000,000 Pa
**********************************************************
TYPICAL VALUES:
On wikipedia typical values for youngs modulus are:
Steel 200 GPa (200 E9 Pa, or 200 X10^9Pa)
Typical Wood 10 GPa (10 E9 Pa, or 10 X10^9Pa)
Glass 72 GPa (72 E9 Pa, or 72 X10^9Pa)
so for Typical Wood that is:
10,000,000,000 Pa as it is in the spreadsheet I believe.
**********************************************************
CONVERSION FROM TABLE ON THIS SITE:
The data in the Kams table is a bit wierd:
The units for youngs modulus should be force / area. The units in the table are in mass / area which is not a valid unit for youngs modulus really. For the conversion I have assumed that 1Kg is equivalent to 10N (this is a commonly used conversion although only valid on earth), so we have:
Table value = 1000Kg/mm^2
=10,000 N/mm^2
=10,000,000,000 N/m^2 (Pa)
This matches the value from Wikipedia so I would assume that you can take the data in the spreadsheet and multiply by 10,000,000 and you have the youngs modulus in Pa which are the units in the spreadsheet.
Like I said the units in the table are a bit wierd because they would imply that the material stiffness would change depending on gravity (which is not true), but this kind of missunderstanding of the difference between mass and force is common so I am 95% sure that the conversion that I have done is correct.
I hope that answers all your questions.
B.