Keep the Heat B/Thermodynamics C

[chalker7]

we have a barrier (with a 1.5 cm hole) that we place into the beaker. it is removable so it doesn't modify the beaker. Could this barrier be placed in before the water is poured, though? it would help save set-up time.

From an earlier clarification I read, I don't think it's allowed for parts of your device to extend below the lip of your beaker.

Which clarification was that and what did it say exactly?

[JTMess]

Not sure where I saw this, but there was a debate about it somewhere, causing us to not use the wood and cotton circle that rested in the top of our beaker. I just spent like 20 mins looking through forums and clarifications for this debate and couldn't find it though, so I'm obviously not a good source to go with for this.

[foreverphysics]

>.<
And this is why bots irritate the living heck out of me. Bad grammar, useless posts, shameless advertising--ugh!
And to return the topic to thermo, has anyone found a way to make your device so that only 1 degree of heat is lost oer 40 minutes? (Starting temp of 69 degrees, room temp of 23, 150 mL) I have heard of a device like that, and I'm kinda...O.O
Bots please go away...

[Flavorflav]

I don't think it's possible with that enormous wind tunnel right over the beaker.

[chalker]

we have a barrier (with a 1.5 cm hole) that we place into the beaker. it is removable so it doesn't modify the beaker. Could this barrier be placed in before the water is poured, though? it would help save set-up time.

From an earlier clarification I read, I don't think it's allowed for parts of your device to extend below the lip of your beaker.

Seeing as how I get copied on all clarifications and FAQ answers for this event (and in fact draft most of them myself), we never said you couldn't have things extend below the lip of your beaker. (Unofficially of course...this isn't the place for official clarifications.. yada yada....)

[haverstall]

Yes, that is one of my questions. Do most competitions have the water transfered from a large hot beaker to the cool 250ml beaker, or is the 250ml beaker already heated?
Also, if you are heating in the water in the 250ml beaker, have you considered evaporation? Some of the water will evaporate by the time it reaches the desired temperature, especially if you are going to 90oC. How do you account for this?

We were lucky in that during the state competition, all the teams had separate Vernier probes, so we took the temp of the water when our time started. Funny thing is that even though they said the water was to be 70 C, it was actually 62.5 C when we measured it. Still to be safe, I would suggest you bring a thermometer yourself, like forever suggested. We did the same, but because of this awesome set up, we didn't have to worry about it.

[Paleofreakazoid]

I'm really sorry if this has been mentioned before, but I was wondering at your state competitions, did they have pre-measured increments of water to pour? Our beaker only measures 25 mL increments, so I was wondering how they would do that at other competitions...

[blazer]

I'm really sorry if this has been mentioned before, but I was wondering at your state competitions, did they have pre-measured increments of water to pour? Our beaker only measures 25 mL increments, so I was wondering how they would do that at other competitions...

At the competitions I've been to, the judges have scooped water out of a large bath, poured it into a graduated cylinder to get the correct volume, and then poured it into my beaker.

[Flavorflav]

As many of these posts attest, the way the judges load the device is the single biggest source of variability in this event. The clarification of 2/21 addresses this problem nicely, by allowing teams to take the internal temperature after loading and before prediction. Unfortunately for us, New York announced at the competition that they did not intend to honor that clarification. Chalkers, do you think that the thermometer could be explicitly allowed in the rules for next year? Predicting exactly how much heat will be lost during a loading procedure that you have limited information about does not seem to me to be the spirit of this event.

[chalker]

As many of these posts attest, the way the judges load the device is the single biggest source of variability in this event. The clarification of 2/21 addresses this problem nicely, by allowing teams to take the internal temperature after loading and before prediction. Unfortunately for us, New York announced at the competition that they did not intend to honor that clarification. Chalkers, do you think that the thermometer could be explicitly allowed in the rules for next year? Predicting exactly how much heat will be lost during a loading procedure that you have limited information about does not seem to me to be the spirit of this event.

It likely will be.