4 ms·
> Perfect graphene can take ~100 Gigapascals (14 million pounds per square > inch) of force before it breaks...imperfect graphene...~4 Megapascals (580 > po
by dfc 13y ago
> Perfect graphene can take ~100 Gigapascals (14 million pounds per square
> inch) of force before it breaks...imperfect graphene...~4 Megapascals (580
> pounds per square inch).
Can anyone put these numbers in perspective? I understand that 100 Gigapascals is a lot, AKA more than anything I personally own. What items does the common person interact-with/own that require > 4 megapascals? I have to imagine that my old titanium lacrosse shaft could handle more than 4 megapascals.
CONTEXT ADDENDUM: Graphene hammer handle versus Hickory Handle?
- dhruvtv 13y ago580 pounds per sq. inch seems a lot for household applications. Say a human were to stand on a Graphene TV, it would be ~250 pounds on ~100 sq. inches, i.e. 2.5 psi.
- stan_rogers 13y agoIt seems like a lot until you take into account a woman of middling weight wearing high(ish) heels, which (when in good condition) often have a "footprint" of about 1/16 of a square inch (and much less if, as is often the case since the lift material doesn't last very long, the heal has been worn through to the pin).
- nether 13y agoSure. 100 GPa is 14.5e6 psi. The pressure of an adult human standing on the ground is 1-2 psi (depending on weight, foot size). Pretty much all metals begin to yield at or less than 40e3-70e3 psi.
- analog31 13y agoI love Google unit conversion. Just enter "100 psi to pascals" as a search phrase and you get an answer. Based on this, it's possible to note some typical things converted into Pascals: Bike tire pressure 100 psi = 690 kPa Tensile strength of 6061 aluminum (the most common alloy) = 45000 psi = 310 MPa
- dfc 13y agoWhenever people say that they like google's unit conversion I like to mention GNU units. I would be surprised if google does a unit conversion that units can not handle. After reading the aluminum statistic it seems that graphene is not going to replace my titanium shaft (that replaced the aluminum shaft).
- ewillbefull 13y agoCan GNU units or anything like it accept a string such as "100F to C" and understand what I'd like? If so I'd love to use that instead.
- dfc 13y agoTemperature conversions are a little goofy because they are nonlinear. Google's 100F to C is: dfc@ronin:~$ units 2866 units, 109 prefixes, 79 nonlinear units You have: tempF(100) You want: tempC 37.777778 The full explanation is here: https://www.gnu.org/software/units/manual/units.html#Temperature-Conversions https://www.gnu.org/software/units/manual/units.html#Tempera...
- Tloewald 13y agoI followed the like because I thought maybe i've been doimg temperature conversioms wrong all my life. Temperature conversions are so linear. They need to use a more correct term — e.g. simply proportional. Having to add or substract a constant before or after scaling does not make a relationship non-linear.
- sixbrx 13y agoThis may be getting pedantic, but the relationship is affine not linear - linear would mean k times the original input would yield k times the original output.
- est 13y agoIt does not convert currencies like Google.
- saraid216 13y agohttp://www.wolframalpha.com/input/?i=4+megapascals http://www.wolframalpha.com/input/?i=4+megapascals