muff528 3 #51 May 24, 2010 Quote Quote so "Degrees Celcius" "Degrees Fahrenheit" "Kelvin" (there is NOT "degrees Kelvin", just Kelvin) What is Rankine? Is it "Degrees Rankine", or just "Rankine" Degrees Rankine is °R Real scientists use K. This scale is the most scientifical: Cold as hell Really fucking cold Cold as a witch's tit Colder than a well digger's ass Ice cold Cold Too cool for school Cool Real nice Warm Hot Piping hot Sweating like a whore in church Hot enough to fry an egg Too hot to handle Hotter'n a two-dollar pistol Hotter than two rats screwin in a whool sock Hotter than a June bride in a feather bed Hot as hell Yeah! I know I skipped some of the graduations. Quote Share this post Link to post Share on other sites
champu 1 #52 May 24, 2010 Quote1. Water is not a gas. For waves in media in general you need to know the density and the elastic stiffness. In ideal gases these are related by the gas law PV = nRT; assume adiabatic conditions then you can get the pressure term to cancel out, and you are left with temperature. Since I happen to have a copy of K, F, C, Sanders within arms reach... assuming adiabatic conditions: sound_velocity^2 = ratio_of_specific_heats * instantaneous_pressure / instantaneous_density ratio_of_specific_heats: air = 1.402 fresh_water = 1.004 sea_water = 1.01 Assuming an ideal gas: instantaneous_pressure = instantaneous_density * specific_gas_constant * temp_in_kelvins specific_gas_constant: air = 287 J / (kg * K) Assuming something other than an ideal gas but with fairly small fluctuations: instantaneous_pressure = equilibrium_pressure + bulk_modulus * ( instantaneous_density - equilibrium_density) / equilibrium_density bulk_modulus: fresh_water = 2.18 * 10^9 Pa sea_water = 2.28 * 10^9 Pa Quote2. There are issues coupling vibrations in water to the ear. Human ears evolved to couple vibrations in air to the cochlea. The ear drum and ossicles make for quite the impedence matching network. I vaguely remember having to calculate the insertion loss and return loss into a human ear in air and underwater. Quote Share this post Link to post Share on other sites
rehmwa 2 #53 May 24, 2010 QuoteK, F, C, Sanders mmmmm - 7 herbs and spices ... Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants Quote Share this post Link to post Share on other sites
champu 1 #54 May 24, 2010 QuoteQuoteK, F, C, Sanders mmmmm - 7 herbs and spices With a name like that can you believe the appendix tables don't include the acoustic properties of gravy? ...as an approximation I can't decide between "castor oil" or "calcareous ooze" Quote Share this post Link to post Share on other sites
rdufokker 6 #55 May 24, 2010 Quote20,000 ft of gravitational acceleration with no drag gives 771 mph. But the speed of sound at around 100K with a standard temp of -70F is 660mph and at 120K where the temperature should actually be higher at around -40F is 684mph. So when he leaves the balloon and falls 30 sec. he should actually be falling into cooler air and the speed of sound decreasing. 660mph is 966 ft/sec. 30 seconds of freefall with no drag is 960 ft/sec. We should start a poll. At what time does he hit his highest Mach speed? My guess is 32 seconds. BurkeIrony: "the History and Trivia section hijacked by the D.B. Cooper thread" Quote Share this post Link to post Share on other sites
timmyfitz 0 #56 May 25, 2010 QuoteQuoteK, F, C, Sanders mmmmm - 7 herbs and spices 11 Quote Share this post Link to post Share on other sites
rdufokker 6 #57 May 30, 2010 Found this from a while back. Very interesting chat we had.Irony: "the History and Trivia section hijacked by the D.B. Cooper thread" Quote Share this post Link to post Share on other sites