Keep the Heat B/Thermodynamics C

[hmcginny]

02/17/2013 - 21:39 Should the students be allowed to place a separate "plug" or "cap" into or on the opening of the internal 250 mL beaker before closing the device?
Yes, teams may put a "plug" or "cap" on the opening of the internal beaker. Anything put in or around the beaker cannot physically modify the beaker nor the water in the beaker. The required hole for the probe must be at least 1.5 cm in diameter in any plug or cap. The device does not need to be all one physically attached unit.

According to this FAQ, you can in fact place a cap into or on the opening of the beaker. Sjwon3789, you are correct, it should be legal as long as there is a 1.5 cm hole for the probe. Devices with full lids are against the rules. I'm enjoying the irony in Forever's comment about not knowing the rules yet

[Paradox21]

You are not allowed to put it directly on the beaker. It must be at least 2.5 cm away from it. If you saw that, then that team was breaking regulations.
That being said, how do you not know the rules yet? Do I need to go over the rules again with you guys before Regs?

Whoa now. The top surface of the thermometer hole must be at MOST 2.5 cm from the top lip of the beaker. This ensures the event supervisor can easily insert the thermometer/probe. You can put a lid over your device, as long as it has a 1.5 cm diameter hole directly above the beaker.

[foreverphysics]

Rule 3c.
You can have a lid, but there must be a large-ish hole. Though, honestly, why would you want anything touching the beaker? Anything useful that could touch the beaker would get soggy and wet, and everything else would be either counterproductive or banned.

[JustDroobles]

Rule 3c.
You can have a lid, but there must be a large-ish hole. Though, honestly, why would you want anything touching the beaker? Anything useful that could touch the beaker would get soggy and wet, and everything else would be either counterproductive or banned.

If you put a "plug" in your beaker, there is less open air around the water. While closed bubbles or pockets of air are good insulators, open air is not. You want to cut down the amount of open air above the beaker that can absorb heat from the water and rise up and carry the heat out of your device. It should not touch the water or get soggy or wet.

[anepictimelord]

Rule 3c.
You can have a lid, but there must be a large-ish hole. Though, honestly, why would you want anything touching the beaker? Anything useful that could touch the beaker would get soggy and wet, and everything else would be either counterproductive or banned.

We have a wool cover with a hole going through it. That way the hot water condenses onto the wool and the heat stays inside the box instead of outside of it

[harryk]

Rule 3c.
You can have a lid, but there must be a large-ish hole. Though, honestly, why would you want anything touching the beaker? Anything useful that could touch the beaker would get soggy and wet, and everything else would be either counterproductive or banned.

We have a wool cover with a hole going through it. That way the hot water condenses onto the wool and the heat stays inside the box instead of outside of it

Same, except mine is cotton

[ychen428]

We were using wool too, but isn't wool forbidden now?

Some examples of materials that ARE considered commercial insulation: • Silverized glass sheets • Cotton batting • Cork paneling • A wool sweater • Glass wool (e.g. fiberglass insulation, the pink fluffy stuff)

[Schrodingerscat]

We were using wool too, but isn't wool forbidden now?

Some examples of materials that ARE considered commercial insulation: • Silverized glass sheets • Cotton batting • Cork paneling • A wool sweater • Glass wool (e.g. fiberglass insulation, the pink fluffy stuff)

However, the same clarification also gives raw wool as an example of an allowed material, so you can still use wool if it is not commercially processed.

[ychen428]

Do you think felt made out of wool is okay, since that's all I've been able to get my hands on.
On the other hand, where did you get raw wool?

[harryk]

Do you think felt made out of wool is okay, since that's all I've been able to get my hands on.
On the other hand, where did you get raw wool?

Wool felt might be iffy. And easiest place to get raw wool from is a sheep