Temerature/pressure ration questions.

[bearandoldman]

As the alt increases the atmospheric pressure drops? yes I know that.
As the atmospheric pressure drops the speed of sound decreases??
As the pressure drops the boiling point of water decreases, that is why they use a pressure cap on automotive colling systems. Also you can not get a good hot cup of coffee on top of Pike's Peak, been there and done that.
Recipes for food preparation at higher altitudes has to be adjusted for time and the amount of water in a recipe. Been theredone that too.
You lose roughly 3% of your car engines horsepower for every 1,000 of altitude gain in a normally aspirated car, been there and experienced that more than once also. .Been too many year since high school Physics class to remember, a little over 60 years now
What happens to the freezing point of water at altitude, does it change or remain the same. Just curious this evening as the temp here is now less than nothing, -4F at present

[Medicine Hat]

http://www.animations.physics.unsw.edu. ... vation.htm
This is about as simple an explanation as I've been able o find. In short, it seems that pressure (not altitude per se) is the issue. Down toward the bottom part of the page, it mentions a condition where water can exist as liquid, vapor, and ice all at the same temperature, and how ice can go from ice, directly to vapor (steam) without passing through a liquid phase.
Must be female...

[bearandoldman]

http://www.animations.physics.unsw.edu. ... vation.htm
This is about as simple an explanation as I've been able o find. In short, it seems that pressure (not altitude per se) is the issue. Down toward the bottom part of the page, it mentions a condition where water can exist as liquid, vapor, and ice all at the same temperature, and how ice can go from ice, directly to vapor (steam) without passing through a liquid phase.
Must be female...

Thanks MH, but no I understand even less, just need a simple oldman answer.

[Medicine Hat]

http://www.animations.physics.unsw.edu. ... vation.htm
This is about as simple an explanation as I've been able o find. In short, it seems that pressure (not altitude per se) is the issue. Down toward the bottom part of the page, it mentions a condition where water can exist as liquid, vapor, and ice all at the same temperature, and how ice can go from ice, directly to vapor (steam) without passing through a liquid phase.
Must be female...

Thanks MH, but no I understand even less, just need a simple oldman answer.

"as we lower pressure, the boiling temperature falls much more rapidly than does the freezing temperature. (For water, the freezing temperature rises slightly at low pressure":

As we go up in altitude, the atmospheric pressure (on earth) becomes less. As the pressure gets less, the boiling point and freezing point both change (temperature-wise), but the freeze point is very much less affected by this, needing super science equipment to detect fhe freeze point change.

[ruger22]

the temp here is now less than nothing, -4F at present

Perfect for trying out one of your newer 10/22s!

[bearandoldman]

the temp here is now less than nothing, -4F at present

Perfect for trying out one of your newer 10/22s!

All the way up to 22+F today, when it gets up to freezing we may do a short range session. Got no new 10/22', right now, have not bought a gun in a month and a half now. Nice thing is the range is only 15 minutes max from the house.

[greener]

The freezing/melting point of water doesn't change much over narrow range of pressures around atmospheric pressure, like going to Pike's Peak. It does decrease as the pressure drops. However, as you get close to a vacuum, water doesn't melt, it sublimes directly to a gas.

As you increase the pressure a lot above atmospheric, the melting point increases. Water/ice/vapor can exist in all three phases at something known as the triple point which is usually 32F at 1 atmosphere

[bearandoldman]

The freezing/melting point of water doesn't change much over narrow range of pressures around atmospheric pressure, like going to Pike's Peak. It does decrease as the pressure drops. However, as you get close to a vacuum, water doesn't melt, it sublimes directly to a gas.

As you increase the pressure a lot above atmospheric, the melting point increases. Water/ice/vapor can exist in all three phases at something known as the triple point which is usually 32F at 1 atmosphere

Thanks Greener my friend. Figured thee Freezing point did not change much but I knew the boiling point did and a14K you can notice the loss of horsepower when you get up there thanks to EFI the motor still runs clean. Can remember the first time I mas there in 1956, my bud was driving his 55 Chrysler New Yorker Deluxe and we damn near did not get to the top, what with black stacking and overtemping both at the same time..

[blue68f100]

On the older computer systems on car/trucks you had to change a jumper under the dash for altitude <3000'. I have not looked at the newer systems to see if they have advanced enough in sensor technology to do it automatically.

[bearandoldman]

On the older computer systems on car/trucks you had to change a jumper under the dash for altitude <3000'. I have not looked at the newer systems to see if they have advanced enough in sensor technology to do it automatically.

My 1991 Chevy Blazer made it up with no problems with it's rudimentary throttle body EFI in I think it was 1995. Blazer hzd z 4.3 V6. Ran perfect through the mountains in Leadville at 10 K and back to Michigan. Did notice the horsepower loss though at 14k, you are down damn close to 42 % of your starting hp.
The 55 Chrysler was of course a big 4 throat carb.